The double-headed parallel ultrasonic welding machine transmits ultrasonic waves to the plastic processing parts through the welding head, so that the two plastic joint surfaces are strongly rubbed by the action of ultrasonic waves, and the friction heat melts the plastic joint surface to complete the gluing. The technology has the advantages of high speed, strong weld seam, etc., and more importantly, it can automate the production and processing of plastic products. Ultrasonic plastic welding machine can be used for plastic welding, embedding, forming, riveting, spot welding, cutting, sewing and other operations. As long as the welding head is changed, it can be used in a variety of applications.