Abstract: Being with high doping concentration and low diffusivity, carbon has emerged as an attractive and promising p-type dopant in Ⅲ-Ⅴ semiconductors, alternative to the conventional acceptors such as Zn and Be for many applications.In this paper, systematically summarizing recent achievements, several aspects of carbon doping and characteristics of carbon doped GaAs and GaAlAs grown by metalorganic vapor phase epitaxy (MOVPE) are discussed and at based on it the applications and further researches of carbon doping are suggested.