As a new nondestructive detection method, Laser ultrasonic, which gradually goes into our sight, is non-contact , point detection and have the significant advantage in high efficiency of complex shape sample test . The article summarized the principle and advantages of Laser Ultrasonic technique, penetration and pulse reflection method were used to test the sample, which was composite laminated containing a preseted damage . The results showed that Ф2mm preset defects could be tested, which can reach the same detection-rate as a ultrasonic test system with a conventional piezoelectric probe.