In this article the last findings of composites with polymer, metal and ceramic matrices containing carbon fibers and their applications in internal combustion engines in the world beside their advantages and superiorities in comparison with common industrial materials are investigated. Afterwards, the position of these materials in automotive engines in Iran is analyzed. Researches show that carbon fibers-reinforced composites due to unique properties (including high specific strength and specific modulus, low thermal expansion coefficient, high fatigue strength, and high thermal stability) can replace common structural materials in different engine parts (such as, casing, different components, cylinder lining, and etc.). Applying these composites will result in weight reduction and consequently fuel consumption reduction, less pollution, better function and efficiency, and more lifetimes. Of course one should consider that there is a vast potential for application and development of composites in automotive engine, which will become in practice by complementary researches through time. Due to novelty of this technology in the world and also the lack of carbon fibers production and insufficient knowledge of production and application of carbon fiber composites in Iran, this issue has not been seriously investigated.