Tadotsu is a town located in Nakatado District, Kagawa Prefecture, Japan. As of 1 October 2022, the town had an estimated population of 22,124 in 10365 households and a population density of 270 persons per km2. The total area of the town is 24.39 square kilometres (9.42 sq mi).

Kagawa Prefecture is a prefecture of Japan located on the island of Shikoku. Kagawa Prefecture has a population of 949,358 and is the smallest prefecture by geographic area at 1,877 square kilometres (725 sq mi). Kagawa Prefecture borders Ehime Prefecture to the southwest and Tokushima Prefecture to the south.