Abstract: Aimed at the problems faced by coal enterprises in safety investment guaranteeing, a safety investment guaranteeing mechanism of "Multi-sides constraint, Better interaction" is constructed for coal enterprises. Based on the "mutual-win" and constraint features of safety investment guarantee system, the guaranteeing function of the government's safety supervision, coal industry association's safety prevention, and insurance company's safety insurance on coal enterprises are analyzed. Then the system dynamics(SD)characteristic of safety investment guaranteeing mechanism is systemically analyzed and demonstrated based on SD theory. On this basis, a system dynamics model of safety investment guarantee mechanism for coal enterprises is set up. This model is to seek a certain safety investment level to ensure the coal enterprise a certain income level, and to improve and optimize the safety investment opportunities and channels of coal enterprises. It is just an attempt to apply SD to assessing the effect of safety investment guarantee mechanism.