diff --git a/hiboo/account/forms.py b/hiboo/account/forms.py
index 3cf2c48314c19ae28bed15c18accb89f78cf869b..2dd7d370dc53a4c2104be50d4080ea98df4501be 100644
--- a/hiboo/account/forms.py
+++ b/hiboo/account/forms.py
@@ -23,7 +23,7 @@ class SignupForm(flask_wtf.FlaskForm):
     username = fields.StringField(
         _('Username'),
         formatter.validators(),
-        description = formatter.message
+        description = (_("The username can be between 3 and 30 characters long. {}".format(formatter.message)))
     )
     password = fields.PasswordField(_('Password'), [validators.DataRequired()])
     password2 = fields.PasswordField(_('Confirm password'),