Atsugi, city, central Kanagawa ken (prefecture), east-central Honshu, Japan. It lies in the Sagami River valley, at the confluence of the Sagami and Nakatsu rivers.
Until the late 19th century, Atsugi flourished as a river port, post town, and centre for sericulture. Now an important commercial centre for the surrounding agricultural region, the city has convenient road and railway connections with Tokyo to the northeast. Its industries include the manufacture of automobile parts and electrical equipment. Atsugi also serves as a tourist base for the Nakatsu and Tsukui valleys. The Sagami River is renowned for its sweetfish, which attract numerous anglers. Pop. (2005) 222,403; (2010) 224,420.