In order to reduce the costs and maximize the profit, many coal mining enterprises are gaming in the safety investment under the coal-mining supervision in China although relative supervision provisions are strict, which results in mine accidents happening. In order to make sense the causes that are behind the economic motivation, based on the gaming model with two variables, technology and cost, in utility function, a safety investment analysis for decision makers is conducted in this paper by focusing on the technological level and production cost in the coal mining enterprises and presenting the gaming process among these enterprises. The result is that there is no enough incentiveness in short term to conduct safety investment under the condition of low technological level in China. Therefore, it is necessary to enhance safety awareness, strengthen supervision and improve safety status of coal production.