Si Chiang Mai (Thai: ศรีเชียงใหม่, pronounced [sǐː t͡ɕʰīa̯ŋ màj]) is a district (amphoe) in the western part of Nong Khai Province, northeastern Thailand. It may also be spelled Sri Chiang Mai.
Si Chiang Mai District was established by King Setthathirath of Lan Xang Kingdom. It was named after Chiang Mai, the hometown of his grandmother, the former queen of Chiang Mai (his mother was the princess from Lan Na). It was created as a district of Nong Khai Province on 4 August 1958, when it was split off from Tha Bo District.