Reducing structural weight is one of the effective ways to maximize the fuel efficiency and to reduce the operational costs for the automotive manufacturers and their suppliers. To realize this goal, automakers are developing some new lightweight materials and integrate them into vehicles. This article introduces some new lightweight materials, such as high flow & high rigidity materials, foam materials and low linear expansion coefficient materials. Recently, in order to reduce vehicle weight, the wall thickness of parts becomes thinner and thinner. For example, the wall thickness of the IP-carrier is from the 3.0 mm to 1.8 mm(40% weight reduction) and the door trim is from 2.5mm to 1.5mm(40% weight reduction), which requires the higher properties of the materials, such as higher flow, higher rigidity and higher impact strength. Besides, the micro-foam materials, prepared by using chemical or physical foaming agents, have many advantages, such as lower density, better size stability, lower fogging and smell, more freedom design. It has been used in many vehicle parts, like door trims, air-conditioning system, IP body, cooling fan and so on. The research shows that there are states: un-complete foaming, perfect foaming and excess foaming in the course of molding chemical micro-foaming process. The control of the competition between the nucleation and growth of bubbles is crucial to manufacture super property micro-foaming material. In addition, replacing steel by plastics is one of the major ways to lighten vehicle parts. However, when assembling, the large difference between the linear expansion coefficients of these two materials has to be overcome. As a result, the lower linear expansion coefficient materials are manufactured. The linear expansion coefficient of these materials is about 2.6x10-5m/m.k, very close to metal. Recently, these materials are mainly used in the tailgate, spoiler, air-inlet grille, wing.