Abstract: A system of ultrasonic stress testing and calibration was established, and respectively using the system and X-ray stress analyzer to detect the residual stress in specimen of Q235 steel, 685 steel, 45 # steel, and aluminum alloy. The comparative study shows that the detected stress values of the two methods aredifferent, but the stress trend isalmost the same. Finally, through using ultrasonic method, we obtain satisfiedapplicationresulton the residual stress testing of weld joint, flat parts, shaft parts,the tube inner wall, bolt, coatingparts,glass and ceramiccomponent, and so on.