357 or .357 may refer to:
.357 Magnum, a firearm cartridge (revolver) .357 SIG, a firearm cartridge (pistol) .357 Remington Maximum, a wildcat firearm cartridge (revolver) .357/44 Bain & Davis, a wildcat firearm cartridge (pistol) .357 Peterbilt, a wildcat firearm cartridge (pistol) .357 Super Magnum, a wildcat firearm cartridge (revolver)
See also 357th (disambiguation) .38 caliber 9 mm caliber