diff --git a/cmd/gf/internal/cmd/cmd_z_unit_gen_dao_test.go b/cmd/gf/internal/cmd/cmd_z_unit_gen_dao_test.go
index 5958e238e4a..0e7a413fecd 100644
--- a/cmd/gf/internal/cmd/cmd_z_unit_gen_dao_test.go
+++ b/cmd/gf/internal/cmd/cmd_z_unit_gen_dao_test.go
@@ -691,3 +691,74 @@ func Test_Gen_Dao_Issue3459(t *testing.T) {
 		}
 	})
 }
+
+// https://github.com/gogf/gf/issues/3749
+func Test_Gen_Dao_Issue3749(t *testing.T) {
+	gtest.C(t, func(t *gtest.T) {
+		var (
+			err        error
+			db         = testDB
+			table      = "table_user"
+			sqlContent = fmt.Sprintf(
+				gtest.DataContent(`issue`, `3749`, `user.tpl.sql`),
+				table,
+			)
+		)
+		dropTableWithDb(db, table)
+		array := gstr.SplitAndTrim(sqlContent, ";")
+		for _, v := range array {
+			if _, err = db.Exec(ctx, v); err != nil {
+				t.AssertNil(err)
+			}
+		}
+		defer dropTableWithDb(db, table)
+
+		var (
+			path  = gfile.Temp(guid.S())
+			group = "test"
+			in    = gendao.CGenDaoInput{
+				Path:  path,
+				Link:  link,
+				Group: group,
+			}
+		)
+
+		err = gutil.FillStructWithDefault(&in)
+		t.AssertNil(err)
+
+		err = gfile.Mkdir(path)
+		t.AssertNil(err)
+
+		// for go mod import path auto retrieve.
+		err = gfile.Copy(
+			gtest.DataPath("gendao", "go.mod.txt"),
+			gfile.Join(path, "go.mod"),
+		)
+		t.AssertNil(err)
+
+		_, err = gendao.CGenDao{}.Dao(ctx, in)
+		t.AssertNil(err)
+		defer gfile.Remove(path)
+
+		// files
+		files, err := gfile.ScanDir(path, "*.go", true)
+		t.AssertNil(err)
+		t.Assert(files, []string{
+			filepath.FromSlash(path + "/dao/internal/table_user.go"),
+			filepath.FromSlash(path + "/dao/table_user.go"),
+			filepath.FromSlash(path + "/model/do/table_user.go"),
+			filepath.FromSlash(path + "/model/entity/table_user.go"),
+		})
+		// content
+		testPath := gtest.DataPath(`issue`, `3749`)
+		expectFiles := []string{
+			filepath.FromSlash(testPath + "/dao/internal/table_user.go"),
+			filepath.FromSlash(testPath + "/dao/table_user.go"),
+			filepath.FromSlash(testPath + "/model/do/table_user.go"),
+			filepath.FromSlash(testPath + "/model/entity/table_user.go"),
+		}
+		for i, _ := range files {
+			t.Assert(gfile.GetContents(files[i]), gfile.GetContents(expectFiles[i]))
+		}
+	})
+}
diff --git a/cmd/gf/internal/cmd/gendao/gendao_dao.go b/cmd/gf/internal/cmd/gendao/gendao_dao.go
index 3d3b8a4d641..753e6daa3b7 100644
--- a/cmd/gf/internal/cmd/gendao/gendao_dao.go
+++ b/cmd/gf/internal/cmd/gendao/gendao_dao.go
@@ -58,8 +58,8 @@ func generateDaoSingle(ctx context.Context, in generateDaoSingleInput) {
 		mlog.Fatalf(`fetching tables fields failed for table "%s": %+v`, in.TableName, err)
 	}
 	var (
-		tableNameCamelCase      = gstr.CaseCamel(strings.ToLower(in.NewTableName))
-		tableNameCamelLowerCase = gstr.CaseCamelLower(strings.ToLower(in.NewTableName))
+		tableNameCamelCase      = formatFieldName(in.NewTableName, FieldNameCaseCamel)
+		tableNameCamelLowerCase = formatFieldName(in.NewTableName, FieldNameCaseCamelLower)
 		tableNameSnakeCase      = gstr.CaseSnake(in.NewTableName)
 		importPrefix            = in.ImportPrefix
 	)
@@ -179,7 +179,7 @@ func generateColumnNamesForDao(fieldMap map[string]*gdb.TableField, removeFieldP
 		}
 
 		array[index] = []string{
-			"            #" + gstr.CaseCamel(strings.ToLower(newFiledName)) + ":",
+			"            #" + formatFieldName(newFiledName, FieldNameCaseCamel) + ":",
 			fmt.Sprintf(` #"%s",`, field.Name),
 		}
 	}
@@ -219,7 +219,7 @@ func generateColumnDefinitionForDao(fieldMap map[string]*gdb.TableField, removeF
 			newFiledName = gstr.TrimLeftStr(newFiledName, v, 1)
 		}
 		array[index] = []string{
-			"    #" + gstr.CaseCamel(strings.ToLower(newFiledName)),
+			"    #" + formatFieldName(newFiledName, FieldNameCaseCamel),
 			" # " + "string",
 			" #" + fmt.Sprintf(`// %s`, comment),
 		}
diff --git a/cmd/gf/internal/cmd/gendao/gendao_do.go b/cmd/gf/internal/cmd/gendao/gendao_do.go
index 16a4c15ebb4..166f9c7cc6a 100644
--- a/cmd/gf/internal/cmd/gendao/gendao_do.go
+++ b/cmd/gf/internal/cmd/gendao/gendao_do.go
@@ -40,7 +40,7 @@ func generateDo(ctx context.Context, in CGenDaoInternalInput) {
 			structDefinition, _ = generateStructDefinition(ctx, generateStructDefinitionInput{
 				CGenDaoInternalInput: in,
 				TableName:            tableName,
-				StructName:           gstr.CaseCamel(strings.ToLower(newTableName)),
+				StructName:           formatFieldName(newTableName, FieldNameCaseCamel),
 				FieldMap:             fieldMap,
 				IsDo:                 true,
 			})
@@ -61,7 +61,7 @@ func generateDo(ctx context.Context, in CGenDaoInternalInput) {
 			ctx,
 			in,
 			tableName,
-			gstr.CaseCamel(strings.ToLower(newTableName)),
+			formatFieldName(newTableName, FieldNameCaseCamel),
 			structDefinition,
 		)
 		in.genItems.AppendGeneratedFilePath(doFilePath)
diff --git a/cmd/gf/internal/cmd/gendao/gendao_entity.go b/cmd/gf/internal/cmd/gendao/gendao_entity.go
index 7a36bf428e7..cb9239dd1e1 100644
--- a/cmd/gf/internal/cmd/gendao/gendao_entity.go
+++ b/cmd/gf/internal/cmd/gendao/gendao_entity.go
@@ -36,7 +36,7 @@ func generateEntity(ctx context.Context, in CGenDaoInternalInput) {
 			structDefinition, appendImports = generateStructDefinition(ctx, generateStructDefinitionInput{
 				CGenDaoInternalInput: in,
 				TableName:            tableName,
-				StructName:           gstr.CaseCamel(strings.ToLower(newTableName)),
+				StructName:           formatFieldName(newTableName, FieldNameCaseCamel),
 				FieldMap:             fieldMap,
 				IsDo:                 false,
 			})
@@ -44,7 +44,7 @@ func generateEntity(ctx context.Context, in CGenDaoInternalInput) {
 				ctx,
 				in,
 				newTableName,
-				gstr.CaseCamel(strings.ToLower(newTableName)),
+				formatFieldName(newTableName, FieldNameCaseCamel),
 				structDefinition,
 				appendImports,
 			)
diff --git a/cmd/gf/internal/cmd/gendao/gendao_structure.go b/cmd/gf/internal/cmd/gendao/gendao_structure.go
index 5603bd3a15a..01f334cb987 100644
--- a/cmd/gf/internal/cmd/gendao/gendao_structure.go
+++ b/cmd/gf/internal/cmd/gendao/gendao_structure.go
@@ -140,7 +140,7 @@ func generateStructFieldDefinition(
 	}
 
 	attrLines = []string{
-		"    #" + gstr.CaseCamel(strings.ToLower(newFiledName)),
+		"    #" + formatFieldName(newFiledName, FieldNameCaseCamel),
 		" #" + localTypeNameStr,
 	}
 	attrLines = append(attrLines, fmt.Sprintf(` #%sjson:"%s"`, tagKey, jsonTag))
@@ -167,6 +167,43 @@ func generateStructFieldDefinition(
 	return attrLines, appendImport
 }
 
+type FieldNameCase string
+
+const (
+	FieldNameCaseCamel      FieldNameCase = "CaseCamel"
+	FieldNameCaseCamelLower FieldNameCase = "CaseCamelLower"
+)
+
+// formatFieldName formats and returns a new field name that is used for golang codes generating.
+func formatFieldName(fieldName string, nameCase FieldNameCase) string {
+	// For normal databases like mysql, pgsql, sqlite,
+	// field/table names of that are in normal case.
+	var newFieldName = fieldName
+	if isAllUpper(fieldName) {
+		// For special databases like dm, oracle,
+		// field/table names of that are in upper case.
+		newFieldName = strings.ToLower(fieldName)
+	}
+	switch nameCase {
+	case FieldNameCaseCamel:
+		return gstr.CaseCamel(newFieldName)
+	case FieldNameCaseCamelLower:
+		return gstr.CaseCamelLower(newFieldName)
+	default:
+		return ""
+	}
+}
+
+// isAllUpper checks and returns whether given `fieldName` all letters are upper case.
+func isAllUpper(fieldName string) bool {
+	for _, b := range fieldName {
+		if b >= 'a' && b <= 'z' {
+			return false
+		}
+	}
+	return true
+}
+
 // formatComment formats the comment string to fit the golang code without any lines.
 func formatComment(comment string) string {
 	comment = gstr.ReplaceByArray(comment, g.SliceStr{
diff --git a/cmd/gf/internal/cmd/testdata/issue/3749/dao/internal/table_user.go b/cmd/gf/internal/cmd/testdata/issue/3749/dao/internal/table_user.go
new file mode 100644
index 00000000000..871b7d65748
--- /dev/null
+++ b/cmd/gf/internal/cmd/testdata/issue/3749/dao/internal/table_user.go
@@ -0,0 +1,85 @@
+// ==========================================================================
+// Code generated and maintained by GoFrame CLI tool. DO NOT EDIT.
+// ==========================================================================
+
+package internal
+
+import (
+	"context"
+
+	"github.com/gogf/gf/v2/database/gdb"
+	"github.com/gogf/gf/v2/frame/g"
+)
+
+// TableUserDao is the data access object for table table_user.
+type TableUserDao struct {
+	table   string           // table is the underlying table name of the DAO.
+	group   string           // group is the database configuration group name of current DAO.
+	columns TableUserColumns // columns contains all the column names of Table for convenient usage.
+}
+
+// TableUserColumns defines and stores column names for table table_user.
+type TableUserColumns struct {
+	Id        string // User ID
+	ParentId  string //
+	Passport  string // User Passport
+	PassWord  string // User Password
+	Nickname2 string // User Nickname
+	CreateAt  string // Created Time
+	UpdateAt  string // Updated Time
+}
+
+// tableUserColumns holds the columns for table table_user.
+var tableUserColumns = TableUserColumns{
+	Id:        "Id",
+	ParentId:  "parentId",
+	Passport:  "PASSPORT",
+	PassWord:  "PASS_WORD",
+	Nickname2: "NICKNAME2",
+	CreateAt:  "create_at",
+	UpdateAt:  "update_at",
+}
+
+// NewTableUserDao creates and returns a new DAO object for table data access.
+func NewTableUserDao() *TableUserDao {
+	return &TableUserDao{
+		group:   "test",
+		table:   "table_user",
+		columns: tableUserColumns,
+	}
+}
+
+// DB retrieves and returns the underlying raw database management object of current DAO.
+func (dao *TableUserDao) DB() gdb.DB {
+	return g.DB(dao.group)
+}
+
+// Table returns the table name of current dao.
+func (dao *TableUserDao) Table() string {
+	return dao.table
+}
+
+// Columns returns all column names of current dao.
+func (dao *TableUserDao) Columns() TableUserColumns {
+	return dao.columns
+}
+
+// Group returns the configuration group name of database of current dao.
+func (dao *TableUserDao) Group() string {
+	return dao.group
+}
+
+// Ctx creates and returns the Model for current DAO, It automatically sets the context for current operation.
+func (dao *TableUserDao) Ctx(ctx context.Context) *gdb.Model {
+	return dao.DB().Model(dao.table).Safe().Ctx(ctx)
+}
+
+// Transaction wraps the transaction logic using function f.
+// It rollbacks the transaction and returns the error from function f if it returns non-nil error.
+// It commits the transaction and returns nil if function f returns nil.
+//
+// Note that, you should not Commit or Rollback the transaction in function f
+// as it is automatically handled by this function.
+func (dao *TableUserDao) Transaction(ctx context.Context, f func(ctx context.Context, tx gdb.TX) error) (err error) {
+	return dao.Ctx(ctx).Transaction(ctx, f)
+}
diff --git a/cmd/gf/internal/cmd/testdata/issue/3749/dao/table_user.go b/cmd/gf/internal/cmd/testdata/issue/3749/dao/table_user.go
new file mode 100644
index 00000000000..9bc9cff6f7d
--- /dev/null
+++ b/cmd/gf/internal/cmd/testdata/issue/3749/dao/table_user.go
@@ -0,0 +1,27 @@
+// =================================================================================
+// This is auto-generated by GoFrame CLI tool only once. Fill this file as you wish.
+// =================================================================================
+
+package dao
+
+import (
+	"for-gendao-test/pkg/dao/internal"
+)
+
+// internalTableUserDao is internal type for wrapping internal DAO implements.
+type internalTableUserDao = *internal.TableUserDao
+
+// tableUserDao is the data access object for table table_user.
+// You can define custom methods on it to extend its functionality as you wish.
+type tableUserDao struct {
+	internalTableUserDao
+}
+
+var (
+	// TableUser is globally public accessible object for table table_user operations.
+	TableUser = tableUserDao{
+		internal.NewTableUserDao(),
+	}
+)
+
+// Fill with you ideas below.
diff --git a/cmd/gf/internal/cmd/testdata/issue/3749/model/do/table_user.go b/cmd/gf/internal/cmd/testdata/issue/3749/model/do/table_user.go
new file mode 100644
index 00000000000..6fe512a4401
--- /dev/null
+++ b/cmd/gf/internal/cmd/testdata/issue/3749/model/do/table_user.go
@@ -0,0 +1,22 @@
+// =================================================================================
+// Code generated and maintained by GoFrame CLI tool. DO NOT EDIT.
+// =================================================================================
+
+package do
+
+import (
+	"github.com/gogf/gf/v2/frame/g"
+	"github.com/gogf/gf/v2/os/gtime"
+)
+
+// TableUser is the golang structure of table table_user for DAO operations like Where/Data.
+type TableUser struct {
+	g.Meta    `orm:"table:table_user, do:true"`
+	Id        interface{} // User ID
+	ParentId  interface{} //
+	Passport  interface{} // User Passport
+	PassWord  interface{} // User Password
+	Nickname2 interface{} // User Nickname
+	CreateAt  *gtime.Time // Created Time
+	UpdateAt  *gtime.Time // Updated Time
+}
diff --git a/cmd/gf/internal/cmd/testdata/issue/3749/model/entity/table_user.go b/cmd/gf/internal/cmd/testdata/issue/3749/model/entity/table_user.go
new file mode 100644
index 00000000000..effe0ce2c54
--- /dev/null
+++ b/cmd/gf/internal/cmd/testdata/issue/3749/model/entity/table_user.go
@@ -0,0 +1,20 @@
+// =================================================================================
+// Code generated and maintained by GoFrame CLI tool. DO NOT EDIT.
+// =================================================================================
+
+package entity
+
+import (
+	"github.com/gogf/gf/v2/os/gtime"
+)
+
+// TableUser is the golang structure for table table_user.
+type TableUser struct {
+	Id        uint        `json:"id"        orm:"Id"        ` // User ID
+	ParentId  string      `json:"parentId"  orm:"parentId"  ` //
+	Passport  string      `json:"pASSPORT"  orm:"PASSPORT"  ` // User Passport
+	PassWord  string      `json:"pASSWORD"  orm:"PASS_WORD" ` // User Password
+	Nickname2 string      `json:"nICKNAME2" orm:"NICKNAME2" ` // User Nickname
+	CreateAt  *gtime.Time `json:"createAt"  orm:"create_at" ` // Created Time
+	UpdateAt  *gtime.Time `json:"updateAt"  orm:"update_at" ` // Updated Time
+}
diff --git a/cmd/gf/internal/cmd/testdata/issue/3749/user.tpl.sql b/cmd/gf/internal/cmd/testdata/issue/3749/user.tpl.sql
new file mode 100644
index 00000000000..59896315c69
--- /dev/null
+++ b/cmd/gf/internal/cmd/testdata/issue/3749/user.tpl.sql
@@ -0,0 +1,10 @@
+CREATE TABLE `%s` (
+    `Id`        int(10) unsigned NOT NULL AUTO_INCREMENT COMMENT 'User ID',
+    `parentId`  varchar(45) NOT NULL COMMENT '',
+    `PASSPORT`  varchar(45) NOT NULL COMMENT 'User Passport',
+    `PASS_WORD`  varchar(45) NOT NULL COMMENT 'User Password',
+    `NICKNAME2`  varchar(45) NOT NULL COMMENT 'User Nickname',
+    `create_at` datetime DEFAULT NULL COMMENT 'Created Time',
+    `update_at` datetime DEFAULT NULL COMMENT 'Updated Time',
+    PRIMARY KEY (`id`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8;
diff --git a/text/gstr/gstr_case.go b/text/gstr/gstr_case.go
index 252db6195bb..88835dd0cdb 100644
--- a/text/gstr/gstr_case.go
+++ b/text/gstr/gstr_case.go
@@ -107,6 +107,7 @@ func CaseConvert(s string, caseType CaseType) string {
 //
 // Example:
 // CaseCamel("any_kind_of_string") -> AnyKindOfString
+// CaseCamel("anyKindOfString")    -> AnyKindOfString
 func CaseCamel(s string) string {
 	return toCamelInitCase(s, true)
 }
@@ -115,6 +116,7 @@ func CaseCamel(s string) string {
 //
 // Example:
 // CaseCamelLower("any_kind_of_string") -> anyKindOfString
+// CaseCamelLower("AnyKindOfString")    -> anyKindOfString
 func CaseCamelLower(s string) string {
 	if s == "" {
 		return s
diff --git a/text/gstr/gstr_z_unit_case_test.go b/text/gstr/gstr_z_unit_case_test.go
index ebf78b59e88..bdc033c0d19 100644
--- a/text/gstr/gstr_z_unit_case_test.go
+++ b/text/gstr/gstr_z_unit_case_test.go
@@ -18,6 +18,7 @@ func Test_CaseCamel(t *testing.T) {
 		{"test_case", "TestCase"},
 		{"test", "Test"},
 		{"TestCase", "TestCase"},
+		{"testCase", "TestCase"},
 		{" test  case ", "TestCase"},
 		{"userLogin_log.bak", "UserLoginLogBak"},
 		{"", ""},