Abstract: Nylon 6 is the early developed species of engineering plastics, its production is one of the largest in polyamide plastic. Modified nylon 6 has been widely used in various fields because of its excellent overall performance. This paper mainly studies the modification of nylon 6. After maleic anhydride grafted elastomers, the compatibility between elastomers and nylon 6 are increased, so do their impct strength. After glass fiber reinforced nylon 6 , the performance index such as tensile strength and bending strength has improved several times. This paper also studies on the influence of the varieties and content of the glass fiber to the properties of composite materials. The results show that when we use high-strength glass fiber whose content is 32.2% , the enhanced mechanical properties of nylon material are excellent. In addition, we toughen and modify nylon 6 to enhance its impact strength deeply. By adding flame retardant into nylon 6, can reinforce insulation of composite materials in which glass fiber adds. In practical applications, we can modify one or more properties of nylon 6 according to the using request, at last ,we can obtain better performance at a lower price.