Kōnan is located in eastern Kanagawa Prefecture, and south of the geographic center of the city of Yokohama.

The area around present-day Kōnan Ward was part of Kuraki District in Musashi Province until the end of the Edo period, and was tenryō territory controlled directly by the Tokugawa shogunate, but administered through various hatamoto.

On October 1, 1927 the area was annexed by the neighboring city of Yokohama, becoming part of Naka Ward.

The Shōnan Electric Railway, the predecessor to the Keikyū Main Line began operations from April 1, 1935 leading to the rapid urbanization of the area.

Kōnan Ward is largely a regional commercial center and bedroom community for central Yokohama and Tokyo.