Abstract: Different types of hidden dangers affect the mining in coal mines' safety and production system, which ultimately determines the system's development. We analyzed the existing problems of Deng's grey correlation method and then computed the correlation degree between different types of hidden dangers and coal mines' production with the T-type correlation degree. The reference sequence was constructed by the coal production which reflects the characteristics of the system meanwhile the comparison sequences were constructed by different types of hidden dangers which affects the system behavior. An empirical analysis was carried out in a coal mine in Shanxi. The result shows that the certain hidden dangers focused on coal mines' production process can be identified with the application of T-type correlation degree method.