The Chanin Building ( CHAN-in), also known as 122 East 42nd Street, is a 56-story office skyscraper in Midtown Manhattan in New York City. It is on the southwest corner of 42nd Street and Lexington Avenue, near Grand Central Terminal to the north and adjacent to 110 East 42nd Street to the west. The building is named for Irwin S. Chanin, its developer.

The structure was designed in the Art Deco style by John Sloan and T. Markoe Robertson of the firm Sloan & Robertson, with the assistance of Chanin's architect Jacques Delamarre. It incorporates architectural sculpture by Rene Paul Chambellan, as well as a facade of brick and terracotta. The skyscraper reaches 680 feet (210 m), with a 649-foot-tall (198 m) roof topped by a 31-foot (9.4 m) spire. The Chanin Building includes numerous setbacks to conform with the 1916 Zoning Resolution.

The Chanin Building was constructed in 1927–1929 on the site of a warehouse, one of the last remaining undeveloped sites around Grand Central Terminal. Upon opening, the building was almost fully rented, and it was the third-tallest building in New York City. Over the years, the upper floors have contained a movie theater, observation deck, and radio broadcast station, while the lower floors were used as offices and a bus terminal. The building was designated a New York City landmark in 1978, and was added to the National Register of Historic Places in 1980.