Folding bicycle with three range speed change box

A folding bicycle with three range speed change box mainly comprises a gearshift mechanism, a handlebar rod, a front fork, a front wheel, a pedal, a seat rod, a folding shaft, a folding mechanism, a gear shifting mechanism, a flat fork, a chain, a rear wheel, a frame and a gearshift stay, wherein the gearshift mechanism is arranged on the handlebar which is connected with the handlebar rod connected with the front fork and the frame, the front wheel is arranged through the front fork via an axis, and the seat rod is connected with the folding mechanism which is connected with the frame via the folding shaft, the lower of the folding mechanism is provided with the gear shifting mechanism which is connected the rear wheel arranged through the flat fork by a chain; the pedal is also connected with the gear shifting mechanism; the gear shifting mechanism and the gearshift mechanism are respectively connected with the gearshift stay. The utility is foldable, has the advantages of fast speed boosting, simple and convenient disassembling, and saving time in particular, and has the function of three range speed, meanwhile, all the gear shifting components are arranged in a close box with engine oil inside for lubricating, thereby avoiding the eroding and blocking of the sewage and dust of wind and rain, and guaranteeing the flexible sliding for a long time.