The invention discloses an integrated in-pipe robot for guided wave detection. The integrated in-pipe robot comprises a telescopic mechanism and two sets of supporting mechanisms. The two ends of the telescopic mechanism are connected with the supporting mechanisms respectively. An air cylinder serves as the telescopic mechanism. A reset spring for piston resetting is arranged in the air cylinder. Each supporting mechanism comprises a cone, wedge blocks, permanent magnets A and permanent magnets B. The two cones are coaxially arranged in the same direction. One cone is connected with a piston rod of the air cylinder. The other cone is connected with a cylinder body of the air cylinder. Every three wedge blocks are arranged on the cone face of the corresponding cone in a sliding mode. The outer side faces of the wedge blocks are arc-shaped faces capable of being matched with the inner side face of a pipeline. The permanent magnets B are fixedly arranged in the wedge blocks respectively. Three permanent magnets A are fixedly arranged at one end of the corresponding cone and correspond to the corresponding permanent magnets B. The magnetism of the adjacent magnetic poles of the permanent magnets A and the permanent magnets B is identical. Piezoelectric probes with certain vibration modes are embedded into the wedge blocks or cones of the supporting mechanisms.