Family name ซัยฟุดดีน (Saifuddin 
, Saifuddeen 
, ซัยฟุดดีน ) , around the world, is a common surname. The family name ซัยฟุดดีน is characteristic of Brunei, where it is quite a common surname, Malaysia, where it is quite a rare surname, and United Arab Emirates. Not in comparison with a country's population, it is commonest in Indonesia, Bangladesh, and Malaysia. More prevalently, ซัยฟุดดีน is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Saifuddin | India, Saudi Arabia, Bangladesh, Malaysia, Indonesia |
| Saifuddeen | United Arab Emirates, Saudi Arabia, Thailand, Nigeria, India |
| ซัยฟุดดีน | Thailand |