Nakatosa is located in the central part of Kōchi Prefecture, on the island of Shikoku, facing the Pacific Ocean to the east.

Kōchi Prefecture Nakatosa has a humid subtropical climate (Köppen Cfa) characterized by warm summers and cool winters with light snowfall.

During the Edo period, the area was part of the holdings of Tosa Domain ruled by the Yamauchi clan from their seat at Kōchi Castle.

The villages of Kure (久礼) and Kaminokae (上ノ加江) and Nishibun (西分村) were established with the creation of the modern municipalities system on October 1, 1889.

In terms of national politics, the town is part of Kōchi 2nd district of the lower house of the Diet of Japan.