During the mining process of Linnancang 11th, 12th coal seam it was found that there was a large content of CO in the fallen coal, experimental results of coal heating and oxidation show that ,at room temperature, the CO appears to decrease first and then increase with the increase of temperature , this phenomenon also confirmed the abnormal emission of CO in the coal. In order to analyze the source of CO, the drilling monitoring and the natural analysis of coal under vacuum are adopted in the field, through continuous monitoring and data processing, it was found that under the condition of low temperature coal begins to release the CO analytic function is derived from the occurrence of coal. Combination of igneous rock distribution area scope, CO content in coal is the largest, near igneous areas away from the area of igneous rock in coal CO stocks fell, initially determined CO source caused by igneous intrusion, the degree of coal metamorphism played a role.