| Sian | |
| Also Known As: | Sihan |
| States: | Malaysia, Brunei |
| Region: | Sarawak |
| Speakers: | 50 |
| Date: | 2000 |
| Ref: | e18 |
| Familycolor: | Austronesian |
| Fam2: | Malayo-Polynesian |
| Fam4: | Melanau–Kajang |
| Fam5: | Outer Central Sarawak |
| Iso3: | spg |
| Glotto: | sian1255 |
| Glottorefname: | Sihan |
Sian (Sihan) is a Kajang language of Brunei and Sarawak.