小坂井町是爱知县东南部的町。为三河地区中面积最小的町，但人口密度高。与丰川市和丰桥市相邻。已于2010年2月1日并入丰川市。

Kozakai(小坂井町,Kozakai-chō) was a town located in Hoi District, Aichi Prefecture, Japan.

As of November 1, 2007, (the last census information available) the town had an estimated population of 22,708 and a population density of 2,188.31 persons per km². The total area was 9.92 km².