Abstract: According to the actual geological data of a coal mine F₂ fault, fault effect, through the method of similar material simulation test, we study the two planes mining on the fault activation effect, stress variation laws of fault and water inrush path. The results show that with the advancing of working face, the fault interface of vertical stress decreases firstly and then increases; in the same advancing step, the stress variation of upper plane interface is greater than that of the fault zone and footwall interface; the middle zone of two planes is affected by two planes mining in turn, the possibility of water inrush is in large possibility.