diff --git a/models/issues/pull.go b/models/issues/pull.go
index 6a1dc3155..a15ebec0b 100644
--- a/models/issues/pull.go
+++ b/models/issues/pull.go
@@ -660,10 +660,10 @@ func GetPullRequestByIssueID(ctx context.Context, issueID int64) (*PullRequest,
 
 // GetAllUnmergedAgitPullRequestByPoster get all unmerged agit flow pull request
 // By poster id.
-func GetAllUnmergedAgitPullRequestByPoster(uid int64) ([]*PullRequest, error) {
+func GetAllUnmergedAgitPullRequestByPoster(ctx context.Context, uid int64) ([]*PullRequest, error) {
 	pulls := make([]*PullRequest, 0, 10)
 
-	err := db.GetEngine(db.DefaultContext).
+	err := db.GetEngine(ctx).
 		Where("has_merged=? AND flow = ? AND issue.is_closed=? AND issue.poster_id=?",
 			false, PullRequestFlowAGit, false, uid).
 		Join("INNER", "issue", "issue.id=pull_request.issue_id").
diff --git a/models/user/user.go b/models/user/user.go
index 454779b9e..82c2d3b6c 100644
--- a/models/user/user.go
+++ b/models/user/user.go
@@ -742,13 +742,13 @@ func VerifyUserActiveCode(code string) (user *User) {
 }
 
 // ChangeUserName changes all corresponding setting from old user name to new one.
-func ChangeUserName(u *User, newUserName string) (err error) {
+func ChangeUserName(ctx context.Context, u *User, newUserName string) (err error) {
 	oldUserName := u.Name
 	if err = IsUsableUsername(newUserName); err != nil {
 		return err
 	}
 
-	ctx, committer, err := db.TxContext(db.DefaultContext)
+	ctx, committer, err := db.TxContext(ctx)
 	if err != nil {
 		return err
 	}
diff --git a/modules/structs/user.go b/modules/structs/user.go
index c5e96f335..f68b92ac0 100644
--- a/modules/structs/user.go
+++ b/modules/structs/user.go
@@ -93,3 +93,12 @@ type UserSettingsOptions struct {
 	HideEmail    *bool `json:"hide_email"`
 	HideActivity *bool `json:"hide_activity"`
 }
+
+// RenameUserOption options when renaming a user
+type RenameUserOption struct {
+	// New username for this user. This name cannot be in use yet by any other user.
+	//
+	// required: true
+	// unique: true
+	NewName string `json:"new_username" binding:"Required"`
+}
diff --git a/routers/api/v1/admin/user.go b/routers/api/v1/admin/user.go
index 4192d8654..369d13943 100644
--- a/routers/api/v1/admin/user.go
+++ b/routers/api/v1/admin/user.go
@@ -461,3 +461,61 @@ func GetAllUsers(ctx *context.APIContext) {
 	ctx.SetTotalCountHeader(maxResults)
 	ctx.JSON(http.StatusOK, &results)
 }
+
+// RenameUser api for renaming a user
+func RenameUser(ctx *context.APIContext) {
+	// swagger:operation POST /admin/users/{username}/rename admin adminRenameUser
+	// ---
+	// summary: Rename a user
+	// produces:
+	// - application/json
+	// parameters:
+	// - name: username
+	//   in: path
+	//   description: existing username of user
+	//   type: string
+	//   required: true
+	// - name: body
+	//   in: body
+	//   required: true
+	//   schema:
+	//     "$ref": "#/definitions/RenameUserOption"
+	// responses:
+	//   "204":
+	//     "$ref": "#/responses/empty"
+	//   "403":
+	//     "$ref": "#/responses/forbidden"
+	//   "422":
+	//     "$ref": "#/responses/validationError"
+
+	if ctx.ContextUser.IsOrganization() {
+		ctx.Error(http.StatusUnprocessableEntity, "", fmt.Errorf("%s is an organization not a user", ctx.ContextUser.Name))
+		return
+	}
+
+	newName := web.GetForm(ctx).(*api.RenameUserOption).NewName
+
+	if strings.EqualFold(newName, ctx.ContextUser.Name) {
+		// Noop as username is not changed
+		ctx.Status(http.StatusNoContent)
+		return
+	}
+
+	// Check if user name has been changed
+	if err := user_service.RenameUser(ctx, ctx.ContextUser, newName); err != nil {
+		switch {
+		case user_model.IsErrUserAlreadyExist(err):
+			ctx.Error(http.StatusUnprocessableEntity, "", ctx.Tr("form.username_been_taken"))
+		case db.IsErrNameReserved(err):
+			ctx.Error(http.StatusUnprocessableEntity, "", ctx.Tr("user.form.name_reserved", newName))
+		case db.IsErrNamePatternNotAllowed(err):
+			ctx.Error(http.StatusUnprocessableEntity, "", ctx.Tr("user.form.name_pattern_not_allowed", newName))
+		case db.IsErrNameCharsNotAllowed(err):
+			ctx.Error(http.StatusUnprocessableEntity, "", ctx.Tr("user.form.name_chars_not_allowed", newName))
+		default:
+			ctx.ServerError("ChangeUserName", err)
+		}
+		return
+	}
+	ctx.Status(http.StatusNoContent)
+}
diff --git a/routers/api/v1/api.go b/routers/api/v1/api.go
index 735939a55..7001dc72a 100644
--- a/routers/api/v1/api.go
+++ b/routers/api/v1/api.go
@@ -1257,6 +1257,7 @@ func Routes(ctx gocontext.Context) *web.Route {
 					m.Get("/orgs", org.ListUserOrgs)
 					m.Post("/orgs", bind(api.CreateOrgOption{}), admin.CreateOrg)
 					m.Post("/repos", bind(api.CreateRepoOption{}), admin.CreateRepo)
+					m.Post("/rename", bind(api.RenameUserOption{}), admin.RenameUser)
 				}, context_service.UserAssignmentAPI())
 			})
 			m.Group("/unadopted", func() {
diff --git a/routers/api/v1/swagger/options.go b/routers/api/v1/swagger/options.go
index 979b18407..0c8d3d353 100644
--- a/routers/api/v1/swagger/options.go
+++ b/routers/api/v1/swagger/options.go
@@ -48,6 +48,9 @@ type swaggerParameterBodies struct {
 	// in:body
 	CreateKeyOption api.CreateKeyOption
 
+	// in:body
+	RenameUserOption api.RenameUserOption
+
 	// in:body
 	CreateLabelOption api.CreateLabelOption
 	// in:body
diff --git a/routers/web/org/setting.go b/routers/web/org/setting.go
index b57ebfbcd..654e9000f 100644
--- a/routers/web/org/setting.go
+++ b/routers/web/org/setting.go
@@ -79,7 +79,7 @@ func SettingsPost(ctx *context.Context) {
 			ctx.Data["OrgName"] = true
 			ctx.RenderWithErr(ctx.Tr("form.username_been_taken"), tplSettingsOptions, &form)
 			return
-		} else if err = user_model.ChangeUserName(org.AsUser(), form.Name); err != nil {
+		} else if err = user_model.ChangeUserName(ctx, org.AsUser(), form.Name); err != nil {
 			switch {
 			case db.IsErrNameReserved(err):
 				ctx.Data["OrgName"] = true
diff --git a/routers/web/user/setting/profile.go b/routers/web/user/setting/profile.go
index f0f053a51..f500be763 100644
--- a/routers/web/user/setting/profile.go
+++ b/routers/web/user/setting/profile.go
@@ -27,9 +27,7 @@ import (
 	"code.gitea.io/gitea/modules/util"
 	"code.gitea.io/gitea/modules/web"
 	"code.gitea.io/gitea/modules/web/middleware"
-	"code.gitea.io/gitea/services/agit"
 	"code.gitea.io/gitea/services/forms"
-	container_service "code.gitea.io/gitea/services/packages/container"
 	user_service "code.gitea.io/gitea/services/user"
 )
 
@@ -57,45 +55,25 @@ func HandleUsernameChange(ctx *context.Context, user *user_model.User, newName s
 		return fmt.Errorf(ctx.Tr("form.username_change_not_local_user"))
 	}
 
-	// Check if user name has been changed
-	if user.LowerName != strings.ToLower(newName) {
-		if err := user_model.ChangeUserName(user, newName); err != nil {
-			switch {
-			case user_model.IsErrUserAlreadyExist(err):
-				ctx.Flash.Error(ctx.Tr("form.username_been_taken"))
-			case user_model.IsErrEmailAlreadyUsed(err):
-				ctx.Flash.Error(ctx.Tr("form.email_been_used"))
-			case db.IsErrNameReserved(err):
-				ctx.Flash.Error(ctx.Tr("user.form.name_reserved", newName))
-			case db.IsErrNamePatternNotAllowed(err):
-				ctx.Flash.Error(ctx.Tr("user.form.name_pattern_not_allowed", newName))
-			case db.IsErrNameCharsNotAllowed(err):
-				ctx.Flash.Error(ctx.Tr("user.form.name_chars_not_allowed", newName))
-			default:
-				ctx.ServerError("ChangeUserName", err)
-			}
-			return err
+	// rename user
+	if err := user_service.RenameUser(ctx, user, newName); err != nil {
+		switch {
+		case user_model.IsErrUserAlreadyExist(err):
+			ctx.Flash.Error(ctx.Tr("form.username_been_taken"))
+		case user_model.IsErrEmailAlreadyUsed(err):
+			ctx.Flash.Error(ctx.Tr("form.email_been_used"))
+		case db.IsErrNameReserved(err):
+			ctx.Flash.Error(ctx.Tr("user.form.name_reserved", newName))
+		case db.IsErrNamePatternNotAllowed(err):
+			ctx.Flash.Error(ctx.Tr("user.form.name_pattern_not_allowed", newName))
+		case db.IsErrNameCharsNotAllowed(err):
+			ctx.Flash.Error(ctx.Tr("user.form.name_chars_not_allowed", newName))
+		default:
+			ctx.ServerError("ChangeUserName", err)
 		}
-	} else {
-		if err := repo_model.UpdateRepositoryOwnerNames(user.ID, newName); err != nil {
-			ctx.ServerError("UpdateRepository", err)
-			return err
-		}
-	}
-
-	// update all agit flow pull request header
-	err := agit.UserNameChanged(user, newName)
-	if err != nil {
-		ctx.ServerError("agit.UserNameChanged", err)
 		return err
 	}
 
-	if err := container_service.UpdateRepositoryNames(ctx, user, newName); err != nil {
-		ctx.ServerError("UpdateRepositoryNames", err)
-		return err
-	}
-
-	log.Trace("User name changed: %s -> %s", user.Name, newName)
 	return nil
 }
 
diff --git a/services/agit/agit.go b/services/agit/agit.go
index b61cb6f3f..32fc3cba4 100644
--- a/services/agit/agit.go
+++ b/services/agit/agit.go
@@ -226,8 +226,8 @@ func ProcReceive(ctx context.Context, repo *repo_model.Repository, gitRepo *git.
 }
 
 // UserNameChanged handle user name change for agit flow pull
-func UserNameChanged(user *user_model.User, newName string) error {
-	pulls, err := issues_model.GetAllUnmergedAgitPullRequestByPoster(user.ID)
+func UserNameChanged(ctx context.Context, user *user_model.User, newName string) error {
+	pulls, err := issues_model.GetAllUnmergedAgitPullRequestByPoster(ctx, user.ID)
 	if err != nil {
 		return err
 	}
diff --git a/services/user/rename.go b/services/user/rename.go
new file mode 100644
index 000000000..af195d7d7
--- /dev/null
+++ b/services/user/rename.go
@@ -0,0 +1,41 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package user
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	user_model "code.gitea.io/gitea/models/user"
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/services/agit"
+	container_service "code.gitea.io/gitea/services/packages/container"
+)
+
+func renameUser(ctx context.Context, u *user_model.User, newUserName string) error {
+	if u.IsOrganization() {
+		return fmt.Errorf("cannot rename organization")
+	}
+
+	if err := user_model.ChangeUserName(ctx, u, newUserName); err != nil {
+		return err
+	}
+
+	if err := agit.UserNameChanged(ctx, u, newUserName); err != nil {
+		return err
+	}
+	if err := container_service.UpdateRepositoryNames(ctx, u, newUserName); err != nil {
+		return err
+	}
+
+	u.Name = newUserName
+	u.LowerName = strings.ToLower(newUserName)
+	if err := user_model.UpdateUser(ctx, u, false); err != nil {
+		return err
+	}
+
+	log.Trace("User name changed: %s -> %s", u.Name, newUserName)
+	return nil
+}
diff --git a/services/user/user.go b/services/user/user.go
index f0b8fe1c3..d52a2f404 100644
--- a/services/user/user.go
+++ b/services/user/user.go
@@ -27,6 +27,22 @@ import (
 	"code.gitea.io/gitea/services/packages"
 )
 
+// RenameUser renames a user
+func RenameUser(ctx context.Context, u *user_model.User, newUserName string) error {
+	ctx, committer, err := db.TxContext(ctx)
+	if err != nil {
+		return err
+	}
+	defer committer.Close()
+	if err := renameUser(ctx, u, newUserName); err != nil {
+		return err
+	}
+	if err := committer.Commit(); err != nil {
+		return err
+	}
+	return err
+}
+
 // DeleteUser completely and permanently deletes everything of a user,
 // but issues/comments/pulls will be kept and shown as someone has been deleted,
 // unless the user is younger than USER_DELETE_WITH_COMMENTS_MAX_DAYS.
diff --git a/templates/swagger/v1_json.tmpl b/templates/swagger/v1_json.tmpl
index c304a7a49..7dc7f563c 100644
--- a/templates/swagger/v1_json.tmpl
+++ b/templates/swagger/v1_json.tmpl
@@ -679,6 +679,46 @@
         }
       }
     },
+    "/admin/users/{username}/rename": {
+      "post": {
+        "produces": [
+          "application/json"
+        ],
+        "tags": [
+          "admin"
+        ],
+        "summary": "Rename a user",
+        "operationId": "adminRenameUser",
+        "parameters": [
+          {
+            "type": "string",
+            "description": "existing username of user",
+            "name": "username",
+            "in": "path",
+            "required": true
+          },
+          {
+            "name": "body",
+            "in": "body",
+            "required": true,
+            "schema": {
+              "$ref": "#/definitions/RenameUserOption"
+            }
+          }
+        ],
+        "responses": {
+          "204": {
+            "$ref": "#/responses/empty"
+          },
+          "403": {
+            "$ref": "#/responses/forbidden"
+          },
+          "422": {
+            "$ref": "#/responses/validationError"
+          }
+        }
+      }
+    },
     "/admin/users/{username}/repos": {
       "post": {
         "consumes": [
@@ -19105,6 +19145,22 @@
       },
       "x-go-package": "code.gitea.io/gitea/modules/structs"
     },
+    "RenameUserOption": {
+      "description": "RenameUserOption options when renaming a user",
+      "type": "object",
+      "required": [
+        "new_username"
+      ],
+      "properties": {
+        "new_username": {
+          "description": "New username for this user. This name cannot be in use yet by any other user.",
+          "type": "string",
+          "uniqueItems": true,
+          "x-go-name": "NewName"
+        }
+      },
+      "x-go-package": "code.gitea.io/gitea/modules/structs"
+    },
     "RepoCollaboratorPermission": {
       "description": "RepoCollaboratorPermission to get repository permission for a collaborator",
       "type": "object",