20th Avenue

20th Avenue or 20 Av may refer to:

• 20th Avenue (Brooklyn), a street in Brooklyn, New York
  • 20th Avenue (BMT Sea Beach Line), subway station serving the N and ​W trains
  • 20th Avenue (BMT West End Line), subway station serving the D train
• 20 Av, the twentieth day of Av, the fifth month of the Hebrew calendar