903 Park Avenue, Residential apartment building on Park Avenue in Upper East Side, United States.

903 Park Avenue is a 17-story residential building at the corner of Park Avenue and East 79th Street on the Upper East Side, with its main entrance on Park Avenue. Designed by architect Robert T. Lyons and erected from 1912 to 1914 by the construction firm Bing & Bing, it rises 188 feet (57 m). At the time of its construction it was said to be the tallest residential building in New York City.

Built from 1912 to 1914 by the construction firm Bing & Bing, 903 Park Avenue was designed by architect Robert T. Lyons alone. At completion it was described as the tallest residential building in New York City. Maria DeWitt Jesup, widow of banker Morris Ketchum Jesup, acquired it in 1914; Vincent Astor bought it in 1917, and Stahl Real Estate owned it by 2002.

The building reflects Park Avenue's transformation into a residential corridor for wealthy families, with its classical design serving as a visual marker of social standing in the neighborhood.

The building is located near the 77th Street and 86th Street subway stations, offering convenient public transit access to the area. Access is limited to residents as it is a private residential building, though the exterior facade can be viewed from the street.

Maria DeWitt Jesup, widow of banker Morris Ketchum Jesup, purchased the entire building immediately upon its completion in 1914. This single ownership of the entire building was an uncommon transaction in the New York real estate market of that era.