diff --git a/api/extensions/ext_mail.py b/api/extensions/ext_mail.py
index 87b15697ba..d2c6e32dfd 100644
--- a/api/extensions/ext_mail.py
+++ b/api/extensions/ext_mail.py
@@ -32,8 +32,6 @@ class Mail:
                 from libs.smtp import SMTPClient
                 if not app.config.get('SMTP_SERVER') or not app.config.get('SMTP_PORT'):
                     raise ValueError('SMTP_SERVER and SMTP_PORT are required for smtp mail type')
-                if not app.config.get('SMTP_USERNAME') or not app.config.get('SMTP_PASSWORD'):
-                    raise ValueError('SMTP_USERNAME and SMTP_PASSWORD are required for smtp mail type')
                 self._client = SMTPClient(
                     server=app.config.get('SMTP_SERVER'),
                     port=app.config.get('SMTP_PORT'),
diff --git a/api/libs/smtp.py b/api/libs/smtp.py
index 17fcc6de7c..6c8e0c2777 100644
--- a/api/libs/smtp.py
+++ b/api/libs/smtp.py
@@ -16,7 +16,8 @@ class SMTPClient:
         smtp = smtplib.SMTP(self.server, self.port)
         if self._use_tls:
             smtp.starttls()
-        smtp.login(self.username, self.password)
+        if (self.username):
+            smtp.login(self.username, self.password)
         msg = MIMEMultipart()
         msg['Subject'] = mail['subject']
         msg['From'] = self._from