Composite materials are gaining acceptance and demand in several commercial markets including sporting goods, construction and transportation. For many of these applications however, such as aircraft, without a reliable damage detection approach, the total cost of ownership may become a limiting factor for the structure s use. Several non-destructive evaluation techniques are compared on the basis of their strengths and weaknesses for in- service testing of composite materials. A procedure has been formulated for identifying and locating of damage in structures using Lamb wave propagation parameters as a base of the health monitoring of composite materials. The main focus was placed on ultrasonic based Lamb waves propagation method.The Ultrasonic based Lamb waves propagation method is totally a new approach for the problem of overlapping of the modes in the analysis of Lamb waves.