Draw-bar box type folding bicycle

The utility model relates to a draw-bar box type folding bicycle which comprises a handlebar assembly, a frame assembly, a wheel assembly, a power part, a braking unit and a saddle. The draw-bar box type folding bicycle is characterized in that the handlebar assembly is composed of an auxiliary handlebar, a handlebar stem, a main handlebar and a quick locking handlebar joint, the frame assembly comprises a front frame, a back frame and a lower beam, wherein the front frame is composed of high-polymer composite sheath and an embedded metal tube, the lower beam is capable of extending and retracting horizontally, a back-wheel rotating mechanism capable of realizing back-wheel rotation is arranged on the back frame, extension portions are integrally arranged on upper portions of the front frame and the back frame, the extension portions of the front frame and the back frame are hinged through a hinged shaft to form an upper beam of the frame assembly, a power assembly comprises a synchronous wheel tooth disk, a crank pedal, a synchronous belt and an embedded synchronous tooth flywheel, and speed ratio of a wheel and the synchronous wheel tooth disk is 5:1. The draw-bar box type folding bicycle has the advantages that rigidity and intensity of the overall frame can be guaranteed, the frame is light in overall weight, and the folding bicycle is quite convenient to carry in traveling, is quick, simple and convenient to fold or unfold, can serve as a transportation tool, and has the function of a travel suitcase.