Sagsai is a sum (district) of Bayan-Ölgii Province in western Mongolia. It is primarily inhabited by ethnic Kazakhs (Altaic Kazakhs). As of 2014 it had a population of 4945 people. The district is home to a large number of eagle hunters who use golden eagles to hunt foxes and hares. Each year, Sagsai hosts the Altai Kazakh Eagle Festival and Sagsai Golden Eagle Festival on the last weekend of September to celebrate its heritage.