| Chiangmai Sign Language | |
| States: | Chiang Mai Thailand |
| Region: | metro Chiang Mai |
| Speakers: | 19 |
| Date: | 2015 |
| Ref: | [1] |
| Familycolor: | Sign language |
| Family: | Chiangmai–Bangkok Sign |
| Iso3: | csd |
| Glotto: | chia1237 |
| Glottorefname: | Chiangmai Sign Language |
Chiangmai Sign Language (also known as Old or Original Chiangmai Sign Language) is a deaf-community sign language of Thailand that arose among deaf people who migrated to Chiang Mai for work or family. The language is moribund, with all speakers born before 1960. Younger generations have switched to Thai Sign Language.