Abstract: To increase the reliability and efficiency of ultrasonic inspection for the boiler heating surfaces, the ultrasonic lamb waves and their applications to the blowing inspection of blowing damages of heating surfaces were studied. The dispersion characteristics of lamb waves were analyzed by solving the dispersion equations in the pipes with a thickness of 4.00mm. The results showed that the echoes of S0 and A0 modes in the end face of non-blowing pipes were superimposed continuously at time domain, while the situation was different in the blowing pipes as the incident angle being 35.2° and the frequency being 500 kHz, and the extent of blowing damages in the pipes was decided by time interval of the two modes. A high accuracy and precision non-destructive testing method for the boiler heating surfaces was provided.