A pentagon is a five-sided polygon.

Pentagon or the Pentagon may also refer to:

• The Pentagon, the headquarters of the United States Department of Defense in Arlington County, Virginia, US
  • United States Department of Defense, as a metonym
  • Pentagon station, a Washington Metro station
• Sanford Pentagon, an indoor sports arena in Sioux Falls, South Dakota

• Pentagon (Brussels), the historical city centre of Brussels, delimited by the "small ring"
• Pentagon (Wiesbaden), the historical city centre of Wiesbaden, Germany
• Pentagon Shopping Centre, a shopping centre in Chatham, Kent, England
  • Pentagon bus station, a defunct bus station located within the Pentagon Shopping Centre
• Pentagono del Buontalenti, in Livorno, Italy

• Pentagon (Japanese band)
• Pentagon (South Korean band)
• The Pentagon (album), a 1976 album by pianist Cedar Walton

• Pentagón, a professional wrestling character in lucha libre
• Pentagón Jr. (born 1985), Mexican masked professional wrestler

• Pentagon (computer), a Soviet clone of the ZX Spectrum computer
• Pentagon Papers, a United States Department of Defense history of the United States' political and military involvement in Vietnam from 1945 to 1967
• 2022–2023 Pentagon document leaks, two sets of leaked classified foreign intelligence documents of the United States
• Pentagon (film), a 2023 Indian Kannada-language film

• Bamboo Pentagon, a mythical secret headquarters of the Viet Cong
• Pentacon
• Pentaconn