Sixth Avenue is a major avenue in New York City's borough of Manhattan. Although the Avenue's official name was changed to Avenue of the Americas in 1945 by Mayor Fiorello La Guardia, New Yorkers seldom use this term.

Traffic on Sixth Avenue moves uptown (northbound). At its southern end, Sixth Avenue intersects Church Street diagonally a few blocks south of Canal Street. Its northern end is at 59th Street (Central Park South) where equestrian bronzes of Simón Bolívar and José Martí flank the traffic entrance to Central Park at Center Drive (closed to traffic during restricted times, such as weekends). What would be Sixth Avenue north of Central Park is called Lenox Avenue or Malcolm X Boulevard.

Sixth Avenue is served by the IND Sixth Avenue subway line. The PATH train to New Jersey also runs under Sixth Avenue. Formerly the elevated IRT Sixth Avenue Line ran up Sixth Avenue, darkening the street and reducing its market value. After the "el" came down, Sixth Avenue was rebuilt during the 1960s as an all-but-uninterrupted avenue of corporate headquarters housed in glass slab towers of International Modernist style, of which the outstanding example is the CBS Building at 52nd Street, by Eero Saarinen (1965), dubbed "Black Rock" from its dark granite piers that run from base to crown with a break; it is Saarinen's only corporate tower.

Sights moving up Sixth Avenue include Greenwich Village, with the polychrome High Victorian Gothic Jefferson Market Courthouse; the surviving stretch of grand department stores of 1880 to 1900 that runs from 14th Street to Herald Square, ending with Macy's department store; Bryant Park followed by the corporate stretch, with the rear of Rockefeller Center and Radio City Music Hall.