The invention discloses an extension tube with the interior provided with a corrugated pipe and the exterior coated with plastic cement. The extension tube comprises an elastic extension tube body, and is characterized in that the pressure-resistant corrugated pipe is arranged in the elastic extension tube body. The extension tube has the beneficial effects that the structure is novel, the application is wide, the floor space is small, use is convenient, dragging is easy, washing is easy, and safekeeping is easy; and meanwhile, the beneficial effects of being resistant to abrasion, high pressure, ultraviolet rays, cold and the like are achieved.