Line 10 of the Beijing Subway is the second loop line in Beijing's rapid transit network as well as the second longest and most widely used line. The line is 57.024 km (35.433 mi) in length, and runs entirely underground through Haidian, Chaoyang and Fengtai Districts, either directly underneath or just beyond the 3rd Ring Road. The Line 10 loop is situated between 2 and 6 kilometres outside the Line 2 loop, which circumnavigates Beijing's old Inner City. Every subway line through the city centre intersects with Line 10, which has 24 transfer stations along route, and 45 stations in all. Line 10's color is capri.

The Beijing Subway is the rapid transit system of Beijing Municipality that consists of 27 lines including 22 rapid transit lines, two airport rail links, one maglev line and 2 light rail lines, and 490 stations. The rail network extends 836 km (519 mi) across 12 urban and suburban districts of Beijing and into one district of Langfang in neighboring Hebei province. With 3.8484 billion trips delivered in 2018, an average of 10.544 million trips per day, the Beijing Subway is the world's busiest metro system. Single-day ridership set a record of 13.7538 million on July 12, 2019. Being 836 kilometres (519 mi) in system length, the Beijing Subway is the longest metro system by route length, surpassing the Shanghai Metro in December 2023.