Abstract: During nondestructive testing by means of electromagnetic acoustic, the testing signal that actually acquired is very complicated, the noise and the interference is very high, so that the useful signal is very low, the amplitude of useful signal and noise signal is basically coincident, SNR and resolution is low. This paper took steel tube for example, designed a processing method on the echo signal that was gained from electromagnetic acoustic transducer. It diminished noise interference, improved SNR and resolution, and achieved the goal of enhancing the effect of electromagnetic acoustic testing. It was proven in practical engineering project that the above mentioned method was necessary and meaningful, and the testing effect was very good, too.