308 or .308 may refer to:

• 308, year 308 AD
• 308 BC
• 308 (number)
• .308 caliber, firearms cartridges with bullet diameters of 0.308 inches (7.62 mm)
  • .308 Winchester, a popular rifle cartridge
• British Rail Class 308, an electric multiple unit train
• Peugeot 308, a small family car
• 308 Polyxo, a main-belt asteroid
• Several cars produced by Ferrari:
  • Ferrari 308 GT4, a sports car
  • Ferrari 308 GTB/GTS, a sports car
• USS William Jones (DD-308) warship
• The 308 cubic inch Holden V8 engine