Congregation Chasam Sopher is an Orthodox synagogue located at 10 Clinton Street on the Lower East Side.

Formed in 1892 by the joining of two congregations of immigrants from Poland, it occupies a Romanesque Revival building constructed in 1853. It is among the oldest surving synagogue buildings in the United States, the second-oldest synagogue building in New York City, and the oldest still in use in the state.