Abstract: The AE testing data of new BOP is difficult to analyze and evaluate. A variety of fatigue test about the BOP shell material was conducted and AE data during the entire test were collected. Through the comparison of different test data, the characteristics of defect extension signal in the material and the characteristics of the typical interference signals were obtained, respectively. Also, the acoustic emission signal trends in the fatigue process of materials were obtained as well. The analysis results were successfully applied to detect new blowout preventer.