The utility model discloses a pipe bending machine. The pipe bending machine comprises a machine frame. An electromotor with a self-braking mechanism is arranged in the machine frame, a belt wheel on a reducer shaft is opposite to a belt wheel on an electromotor shaft, a gear on the reducer shaft is meshed with a gear on a drive shaft, a swing plate and a second idler wheel are arranged on the portion, stretching out of a platen, of the drive shaft, the outer end of the swing plate is provided with a first idler wheel which is opposite to the second idler wheel, the two ends of a tension spring are connected with the swing plate and the platen respectively, the right end face of a pressing plate is flush with the axis of the drive shaft, the surface of the front side of the pressing plate and the lower edge of the first idler wheel at the upper end of the swing plate are on the same horizontal plane, the distance between the surface of the front side of the pressing plate and the upper edge of the second idler wheel is the same as the diameter of a pipe, a touch plate is arranged on the drive shaft and is opposite to a travel switch on the machine frame, and the travel switch is connected to a circuit between the electromotor and a power supply in series. The pipe bending machine has the remarkable advantages of being high in efficiency and good in quality.