Robert Ferdinand Wagner, Jr., usually known as Robert F. Wagner, Jr. (1910–February 12, 1991) served three terms as the mayor of New York City, from 1954 through 1965. He was born in Manhattan, New York, the son of United States Senator Robert F. Wagner. Wagner attended Yale University, where he became a member of Scroll and Key.

Wagner served in the State Assembly (1937–1941) and as Borough President of Manhattan (1950–1953). He served as delegate to conventions and was nominated for the Senate and the Vice-Presidency. During World War II, he served in the Army Air Corps.

His nomination and election as New York City mayor in 1953 caused a rift in the Democratic Party, and instigated a long-standing feud between Eleanor Roosevelt and Carmine DeSapio, Boss of Tammany Hall.

During Wagner's tenure as mayor of New York, he built public housing and schools, created the City University of New York system, established the right of collective bargaining for city employees, and barred housing discrimination based on race, creed or color. He was the first mayor to hire significant numbers of people of color in city government. His administration also saw the development of the Lincoln Center and brought Shakespeare to Central Park.

After deciding not to run for a fourth term in 1965, Wagner served as ambassador to Spain from 1968 to 1969. He died in Manhattan of heart failure in 1991. The Robert F. Wagner Graduate School of Public Service at New York University is named in his honor.