谢尔加奇 （俄语：Серга́ч）是俄罗斯下诺夫哥罗德州东南部的一个城市、谢尔加奇斯基县县治。位于皮亚纳河畔，距下诺夫哥罗德东北150公里。2002年人口22,887人。

1649年首见于文献，1779年设市。

Sergach (Russian:Серга́ч) is a town and the administrative center of Sergachsky District in Nizhny Novgorod Oblast, Russia, located on the Pyana River (Sura's tributary), 150 kilometers (93 mi) southeast of Nizhny Novgorod, the administrative center of the oblast. Population: 21,386(2010 Census);22,887(2002 Census);25,231(**** Census).