C37 or C-37 may refer to:

Vehicles

;Aircraft

  • Caudron C.37, a French passenger biplane
  • Cessna C-37, an American civil utility aircraft
  • Gulfstream Aerospace C-37A, an American military VIP passenger jet based on the Gulfstream V
  • Gulfstream Aerospace C-37B, an American military VIP passenger jet based on the Gulfstream G550
  • Lockheed C-37 Electra, an American military transport

;Automobiles

  • Dongfeng Sokon C37, a Chinese van
  • Marshall C37, a British bus
  • Sauber C37, a Swiss Formula One car

;Ships

  • Corsair 37, an American trimaran sailboat
  • , a C-class submarine of the Royal Navy
  • Catalina 37, a yacht produced by Catalina Yachts

Other uses

  • C37 road (Namibia)
  • Caldwell 37, an open cluster
  • King's Gambit, a chess opening
  • Route C37 (Massachusetts), a street in Boston
  • SARS-CoV-2 Lambda variant, also known as lineage C.37