Abstract: This paper introduces the principle, technical characteristics and application prospect of Compton backscatter technology in SRM testing. According to the structure of the SRM chamber, simulated samples of debonding defect in the chamber were prepared. The ComScan 160ⅡCompton backscatter imaging system was used to test the simulated samples. The results show that the Compton backscatter imaging system can effectively test the defects in the first and second interfaces of the solid rocket motor, as well as the internal debonding in the insulation layer. Therefore, the Compton backscatter imaging system has the obvious advantage in testing the surface and near surface defects of the composite materials in one side, and opens up the possibility for testing the large products.