Kaiyuan Subdistrict is a subdistrict of Siming District, Xiamen, Fujian Province, People's Republic of China. It covers an area of and has a registered population of 63,362.
It is located in central Xiamen Island, north of the original Siming District and south of Huli District. It is named after a street meaning "Initiating the First (Year)".
In October 1945, Kaiyuan was created as a district (Kaiyuan District 開元區) along with Zhongxin District (Chinese: 中心區) Gulangyu District (Chinese: 鼓浪嶼區) and Heshan District (Chinese: 禾山區). In August 1966, it was renamed Dongfeng (lit. East Wind) District (Chinese: 东风), but this was reverted in October 1979. Finally, in April 2003, Kaiyuan and Gulangyu Districts were merged into Siming District.