The purpose of this paper is to investigate the detection method of composite laminates by using digital shear speckle interferometry, and to establish an experimental and simulation system to verify the test results. The effectiveness of the detection method is verified by comparing to the X-ray inspection technology and ultrasonic C-scan test results. The effectiveness of the proposed method is verified by analyzing the testing results of different curvature laminates. In addition, the concept of relative deformation phase threshold is proposed as a criterion for judging whether a defect can be successfully detected. According to this standard, the defect detection capability under different temperature loading conditions can be inferred, therefore to guide the actual loading parameters of the digital shear speckle technique.