Last name سیان (Sian 
, Siyan 
, سیان 
) , across the world, is a common surname. The surname سیان is characteristic of Malaysia, where it is quite a common surname, Guatemala, and Myanmar, where it is quite a rare surname. Not in comparison with a country's population, it is the most numerous in Malaysia, Guatemala, and Indonesia. Also, سیان is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Sian | United Kingdom, Guatemala, Malaysia, Indonesia, Myanmar |
| Siyan | United Kingdom, China, Malaysia, Indonesia, Myanmar |
| سیان | Iraq |