Abstract: CT detection is an important method to find the common defects of interlaminar debonding in large solid rocket motor. A finite angle CT technique for detecting debonding defects of solid rocket motor was described, the feasibility and practicability of the technique were verified by the finite angle CT scanning of the local debonding defect of the engine in the fixed state with the panel array detector and the high-precision linear motion accelerator. The test results showed that the local CT technique was more sensitive to the desticking and delamination defects parallel to the ray source direction, and could detect the desticking defects with a minimum thickness of 0.4 mm, but the detection results of the crack and cavity defects perpendicular to the ray source direction are not ideal.