扎因斯克（俄语：Заи́нск、鞑靼语：Зәй）是俄罗斯鞑靼斯坦共和国西南部的一个城市，位于扎伊河畔，距首府喀山以东287公里。2002年人口41,088人。

1978年设市并改名。

Zainsk (Russian:Заи́нск; Tatar: CyrillicЗәй, LatinZäy) is a town in the Republic of Tatarstan, Russia, located on the Stepnoy Zay River (Kama's tributary), 287 kilometers (178 mi) east of Kazan. Population: 41,803(2010 Census);41,088(2002 Census);36,621(**** Census).