| Official Name: | San Sai |
| Native Name: | สันทราย |
| Subdivision Type: | Country |
| Subdivision Name: | Thailand |
| Subdivision Type2: | Province |
| Subdivision Name2: | Chiang Mai |
| Subdivision Type3: | District |
| Subdivision Name3: | Fang |
| Population As Of: | 2005 |
| Population Total: | 11583 |
| Timezone: | ICT |
| Utc Offset: | +7 |
San Sai (Thai: สันทราย) is a tambon (subdistrict) of Fang District, in Chiang Mai Province, Thailand.[1] In 2005 it had a population of 11,583 people. The tambon contains 17 villages. The subdistrict is the home of Fangchanupathum School.