Abstract: Coal inventory is influenced by many factors whose influence is different. This paper focuses on influential factors in China coal inventory grey correlation model, which are mainly transportation, demand, supply, prices, and import, export. Coal inventory grey correlation models of power plant, port, and enterprise are established. By utilizing monthly data in the period from Jan 2011 to Sep 2014, it is generally believed that among those factors, coal imports, railway transport volume are the most significant ones. For further discussion of the long-run equilibrium relationship between coal inventory and the factors, the co-integration test between the three kinds of coal inventories and the two most important factors are respectively taken. The results show that there is a long-term equilibrium relationship between the port coal stock and those two factors. In the end, according to the international and domestic coal market situation, the results of grey model have been profound analyzed and useful management advice has been presented.