The invention belongs to the field of 3D printing and discloses a high-capacity rotatable FDM spray head. The spray head comprises a steering gear, a feeding pipe, a throat pipe, a heating block, a cooling mechanism and a nozzle; the steering gear drives the spray head to rotate; the heating block heats materials in the nozzle to a molten state; the cooling mechanism on the feeding pipe is used for lowering the temperature of the materials in the feeding pipe; under the action of the heating block and the cooling mechanism, normal discharge of the nozzle is ensured, and material blockage in the feeding pipe is avoided; a square column is arranged under the nozzle; and the square column is provided with an L-shaped discharge port, thus, the molten materials are simultaneously extruded fromthe side and the bottom of the square column, stress is relieved on the one hand, and stress concentration and blocking due to discharge from the bottom are avoided. Through the high-capacity rotatable FDM spray head, the printing efficiency is improved, the problems of thermal stress warping and liable nozzle blockage are solved, efficient part printing is ensured, and meanwhile, the strength andcompactness of printed parts are improved to some extent.