The invention provides an automatic plastic tube bending machine which comprises a working table, a leveling mechanism, a feeding mechanism, a heating mechanism, a hold-down mechanism, a cutting mechanism, a bending mechanism, a shaping mechanism and a discharging manipulator mechanism sequentially arranged on the working table according to the manufacturing procedure. The working procedures of straightening, cutting, heating, clamping and bending a plastic tube and getting material are combined, and all operations are finished on one equipment, so that the working procedures can be consistently finished, and the automatic plastic tube bending machine is low in production cost, high in efficiency and small in occupied area, can automatically bend the plastic tube, and saves time and labor.