The invention discloses a self-carburizing combustor. The self-carburizing combustor comprises a gas pipe, an oxygen pipe and a self-carburizing pipe. A natural gas inlet is formed in the gas pipe, and a combustion end of the gas pipe extends into the oxygen pipe and generates a combustor flame. The oxygen pipe sleeves the gas pipe, an oxygen inlet is formed in the oxygen pipe, and a circular oxygen passageway communicated with the oxygen inlet is formed between the outer all of the gas pipe and the inner wall of the oxygen pipe. One end of the self-carburizing pipe extends into the gas pipe, a self-carburizing oxygen inlet is formed in the self-carburizing pipe, and a combustion end of the self-carburizing pipe generates a self-carburizing flame. The self-carburizing combustor is simple in structure and low in cost, blackness and brightness of flames can be increased without addition of extra equipment, radiation efficiency is increased, and generation of oxynitride is avoided.