Yanchi is a town in the northern part of Mentougou District, Beijing, China. It lies in the mountainous western outskirts of the municipality, well away from the dense central urban area.
The town is bordered by Liucun Town and Huailai County to the north, Miaofengshan and Wangping Towns to the east, Datai Subdistrict to the south, and Zhaitang Town to the west. Its position on the boundary with Huailai County places it near the edge of the Beijing municipality.
Yanchi had a population of 5,160 as of 2020. It is one of several small towns that make up the rural and semi-rural northern section of Mentougou District.