The utility model provides a cooling structure of a battery module, and belongs to the technical field of battery cooling. The problem that an existing battery module is poor in heat dissipation efficiency is solved. The cooling structure of the battery module comprises a cooling base used for accommodating a battery module cell, wherein the cooling base comprises cooling side plates used for being in contact with two side surfaces of the battery module cell and a cooling bottom plate used for being in contact with the bottom surface of the battery module cell. According to the cooling structure, through a three-side cooling mode, the heat dissipation efficiency of the battery module is greatly improved, and the service life is greatly prolonged; meanwhile, the battery module is simple instructure and convenient to assemble.