The utility model relates to a special trailer for a blowout preventer, and the trailer comprises a truck chassis and a turning device, wherein the truck chassis comprises a middle crossbeam and a rear crossbeam with a U-shaped or V-shaped cross section; the turning device comprises a hydraulic cylinder and a turning support with a T-shaped cross section, wherein the cylinder end of the hydraulic cylinder is hinged onto the side surface of the middle crossbeam, and the piston rod end of the hydraulic cylinder passes through a space above the rear crossbeam and is hinged to the middle end of the turning support; the rotary end of the turning support is hinged at the lowest position of the rear crossbeam, and a plane for fixing the blowout preventer is formed between the free end and middle end of the turning support. The blowout preventer is fixedly arranged on the plane for fixing the blowout preventer through a bolt. The hydraulic cylinder extends to drive the turning support to turn, the automatic operation to the blowout preventer is realized, and the conversion between a transportation state and an installation state can be realized without the help of the swinging of a crane.