Full-automatic barrier-free passing device capable of being used for bus

The invention relates to a full-automatic barrier-free passing device capable of being used for a bus. The device comprises a mounting base, a combined sliding rail mechanism, a retracting and releasing mechanism, a lifting mechanism and a connecting plate assembly, wherein the mounting base is fixedly connected with a bus chassis; the left and right sets of combined sliding rail mechanisms are symmetrically arranged on two sides of the mounting base; the two sets of folding and unfolding mechanisms and the two sets of combined sliding rail mechanisms are connected and correspondingly arranged; the lifting mechanism is arranged on the inner side of the retracting mechanism; a connecting plate assembly is arranged above the lifting mechanism; the mounting base is fixed to a chassis of a rear door of a bus, the direct-current motor serves as a working power source, the ground serves as a main stress point when the device works, passengers are sent into and sent out of the bus through thelifting mechanism and th