Located in far southern Saitama Prefecture, Asaka in the center of the Musashino Terrace on the central reaches of the Arakawa River, which runs along the city border with Saitama in the northeastern part of the city, Asaka has a humid subtropical climate (Köppen Cfa) characterized by warm summers and cool winters with light to no snowfall.

The area of modern Asaka developed as a series of four post stations on the Kawagoe Kaidō highway from the Muromachi period onwards.

Following the Meiji restoration, the village of Hizaori was created within Niikura District, Saitama with the establishment of the modern municipalities system on April 1, 1889.

At the 1964 Summer Olympics in neighboring Tokyo, the town hosted the riding part of the modern pentathlon event at Asaka Nezu Park.

Asaka has a mayor-council form of government with a directly elected mayor and a unicameral city council of 24 members.