The rail-type container gantry crane is composed of main beam, rigid and flexible door legs, traveling trolley, lifting mechanism, crane traveling mechanism, electrical system, operating cab, etc. According to the operation process of the storage yard, the cantilever extended in the direction of single or double gate legs becomes a single cantilever or double cantilever type, and the non-cantilever type becomes a non-cantilever type. According to the site, the container storage and transportation process and the loading and unloading vehicles (container trucks or railway vehicles), different structural forms of non-cantilever, single-cantilever and double-cantilever are determined.