Kushimoto is bordered by the towns of Susami on the west, Kozagawa on the north, and Nachi-Katsuura on the east.
Kushimoto (or specifically, Shiono-Misaki) was the epicenter of the Great Nankai Earthquake, a magnitude 8.0 earthquake that struck the area on December 21, 1946 at 4:19am.
Of the 269 casualties in Wakayama Prefecture, the majority were in Kushimoto and in the city of Kainan.
On October 1, 2004, the village of Minabegawa and the town of Minabe {both from Hidaka District) merged to form the new town of Minabe.
On April 1, 2005, the town of Kushimoto from Nishimuro District merged with the town of Koza from Higashimuro District to form the town of Kushimoto (now part of Higashimuro District).
On April 1, 2005, the city of Kainan and the town of Shimotsu from Kaisou District merged to form the new city of Kainan.