Abstract: With coal mine mechanization degree enhanced unceasingly in China, the mining speed accelerated incessantly, CO overrunning problems became more and more obvious. In this paper, it introduced the necessity of CO overrunning research, and then it presented the research status and progress of CO overrunning research in China. Moreover, it analyzed the several sources of CO in coal mine, summarized the research status of CO overrunning in coal mine, it tentatively discussed the development trend of CO overrunning research.