The utility model discloses a universal joint for a pipeline detector, which comprises a universal joint arm, the two ends of the universal joint arm are respectively and movably connected with a universal joint seat, the two ends of the universal joint arm are respectively provided with a rotating groove, a rotating column is rotationally arranged in each rotating groove, and one end of each rotating column rotationally extends to the outer part of the universal joint arm; a connecting block is fixedly connected to the side, close to the universal joint arm, of the universal joint base, a rotating base is fixedly installed on the side, close to the universal joint arm, of the connecting block, and a universal ball groove is formed in the side, close to the connecting block, of the rotating base. Compared with the prior art, the universal joint for the pipeline detector has the advantages that the rotation angle is larger, the rotation angle is further enlarged, the fluency during angle rotation is improved, the flexibility during angle rotation of the universal joint is improved, the passing rate of a small-curvature-radius pipeline elbow is further improved, and the universal joint is suitable for application and popularization.