Abstract: Aiming at the problem that there was no machining allowance in the thickness dimension and considering defects feature for composite material laminate, a composite material laminate testing block of artificial defects with various dimensions and indepth was designed, 100% scanning was conducted for the testing block using the method of the ultrasonic phased array testing. The Cscan image showed that all artificial defects could be detected and the minimum  3 mm defect located between first and second layer of carbon cloths could be clearly detected. The practical application showed that the method could be used for the NDT of composite material laminate.