Kozagawa (古座川町, Kozagawa-chō) is a town located in Higashimuro District, Wakayama Prefecture, Japan.

Kozagawa has a Humid subtropical climate (Köppen Cfa) characterized by warm summers and cool winters with light to no snowfall.

Kozagawa has a mayor-council form of government with a directly elected mayor and a unicameral city council of 10 members.

In terms of national politics, the town is part of Wakayama 3rd district of the lower house of the Diet of Japan.

Because of warm and wet climate, from ancient times, good-quality woods, called "Kozagawa-Zai (古座川材)", have been produced.