MG Double-beam truss gantry crane is comprised of gantry, crane crab, trolley travelling mechanism, cab and electric control system.The gantry, of a truss structure and having advantages of light structure, strong wind resistance and so on, is composed of girder,upper end girder, leg, lower end girder, travelling trolley and platform railing. The girder is of a triangular truss structure, on which laid rails for crane crab to transversely move along the girder. The legs, of a truss structure, are weld by section steel. The platform, which is used to place electric equipment and used for repair, is furnished with protection railing outside. The closed cab is employed for operation, where there are adjustable seat, insulating mat on the floor, toughened glass for the window, fire extinguisher, electric fan and auxiliary equipment such as air conditioner, acoustic alarm and interphone which can be furnished as required by users.