diff --git a/routers/secure/user.go b/routers/secure/user.go
index 8567dc9e6..d5b303d5e 100755
--- a/routers/secure/user.go
+++ b/routers/secure/user.go
@@ -7,6 +7,7 @@ package secure
 
 import (
 	"net/http"
+	"net/mail"
 	"strings"
 
 	"code.gitea.io/gitea/models"
@@ -63,6 +64,14 @@ func CreateUser(ctx *context.Context, form api.CreateUserOption) {
 	//   "422":
 	//     "$ref": "#/responses/validationError"
 
+	_, err1 := mail.ParseAddress(form.Email)
+	if err1 != nil {
+		ctx.JSON(http.StatusBadRequest, map[string]string{
+			"error_msg": "Email format is wrong.",
+		})
+		return
+	}
+
 	u := &models.User{
 		Name:               form.Username,
 		FullName:           form.FullName,