Kawasoe (川副町 Kawasoe-machi) was a town located in Saga District, Saga, Japan.
On October 1, 2007 Kawasoe, along with the towns of Higashiyoka and Kubota, all from Saga District, was merged into the expanded city of Saga.
As of 2006, the town had an estimated population of 18,492 and a density of 398 persons per km². Its total area was 46.49 km².
Saga Airport is located in the former territory of Kawasoe.