The Eldridge Street Synagogue is an Orthodox Jewish synagogue at 12 Eldridge Street, in the Chinatown and Lower East Side neighborhoods of Manhattan in New York City, New York, U.S. Built in 1887 for Congregation Kahal Adath Jeshurun, the synagogue is one of the first erected in the U.S. by Eastern European Jews. The congregation, officially known as Kahal Adath Jeshurun with Anshe Lubz, still owns the synagogue and hosts weekly services there in the 21st century. The Museum at Eldridge Street, founded in 1986 as the Eldridge Street Project, also occupies the synagogue under a long-term lease. The building is a National Historic Landmark and a New York City designated landmark.

The Lower East Side, sometimes abbreviated as LES, is a historic neighborhood in the southeastern part of Manhattan in New York City. It is located roughly between the Bowery and the East River from Canal to Houston streets. Historically, it was understood to encompass a much larger area, from Broadway to the East River and from East 14th Street to Fulton and Franklin Streets.