The invention provides a lifting rail-changing type single-rail urban rail system based on an APM. The system includes a rack, a rail arranged on the rack, and an APM passenger service vehicle; the rail comprises an accelerating rail body and a main rail body, and the main rail body includes a horizontally arranged chain type rotary rail, two main gears meshed with the chain type rotary rail, a driving mechanism driving the main gears to rotate, and a rail fastening device used for fastening the bottom of the APM passenger service vehicle and the chain type rotary rail; the main rail is an overhead monorail. The system can effectively relieve urban traffic operation pressure and realize the light weight and miniaturization of a passenger train.