Abstract: In order to improve the predicting accuracy of mining subsidence,to explain the phenomena which the subsidence coefficient is larger than 1,and to decrease the mining damage,on the basis of bore-hole measuring of dynamic water level results,the 3 kinds of relations between overburden failure and de-watering of water-holding strata is obtained.The void ratio may decrease with the increasing of effective stresses after water losing.The mechanism of consolidation subsidence due to de watering of water-bearing strata is established.The calculation method of surface subsidence caused by underground mining and de-watering is derived using superposition principle.The example demonstrates that the consolidation subsidence due to de-watering accounts for 25% of the coal seam mining subsidence.