The 21st Street station is a station on the IND Crosstown Line of the New York City Subway. Located at the intersection of 21st Street and Jackson Avenue in the Hunters Point section of Long Island City, Queens, it is served by the G train at all times.

The IND Crosstown Line or Brooklyn–Queens Crosstown Line is a rapid transit line of the B Division of the New York City Subway in Brooklyn and Queens, New York City, United States. It provides crosstown service between western Brooklyn and northwestern Queens and is the only subway line that does not carry trains to and from Manhattan.