The New York Civil Liberties Union (NYCLU) is a civil rights organization in the United States. Founded in November 1951 as the New York affiliate of the American Civil Liberties Union, it is a not-for-profit, nonpartisan organization with nearly 50,000 members across New York State.

NYCLU's stated mission is to defend and promote the fundamental principles and values embodied in the Bill of Rights, the U.S. Constitution and the New York State Constitution, including freedom of speech, freedom of religion, and the right to privacy, equality and due process of law for all New Yorkers. NYCLU performs its work through litigation, advocacy, community organizing, and public education.

The NYCLU has eight offices in New York State: Central New York (the Syracuse area), the Capital Region (the Albany area), Lower Hudson Valley, Suffolk County, Nassau County, New York City, Genesee Valley and the Western Region. The New York City office is the organization's headquarters and represents all regions that do not have their own local chapter or regional office.

Donna Lieberman has been the executive director of the NYCLU since December 2001.