Yorktown is a town in Westchester County, New York, in the suburbs of New York about 38 miles north of midtown Manhattan. The town lies on the north border of Westchester County. The population was 36,081 at the 2010 census.

Yorktown has a rich historical heritage beginning with the earliest known inhabitants — Mohegan, Osceola, Amawalk, Kitchawan and Mohansic — all familiar names of local places. Most of Yorktown was part of the Manor of Cortlandt, a Royal Manor established by King William III for the Van Cortlandt family. The Croton River, which runs through the southern part of Yorktown, was dammed by New York City to provide its first major source of clean and reliable water.
The north town line is the border of Putnam County, New York. The town of Somers borders Yorktown on the east, and Cortlandt borders Yorktown on the west. New Castle borders Yorktown on the south.

According to the United States Census Bureau, the town has a total area of 39 square miles.

As of the 2010 census of 2010, there were 12,556 households, and 9,831 families residing in the town.

Yorktown Heights is home to the IBM Thomas J. Watson Research Center and the Guiding Eyes for the Blind headquarters.

The town hosts the yearly Greasestock festival, a showcase of alternative fuel vehicles.

Yorktown once had five stations along the New York and Putnam Railroad — Kitchawan, Croton Lake, Croton Heights, Yorktown Heights and Amawalk. The railroad failed, was purchased by the New York Central, and was finally abandoned. The old right of way is now part of the North County Bike Trailway which runs north as far as Carmel, New York. There is currently no rail service in Yorktown, but there are multiple Metro-North Railroad stations nearby. Yorktown Stage is regularly recognized as a fan favorite in the county for Community Theater, winning the honor of "Best in Family Entertainment" from Westchester Magazine.