Abstract: Based on the engineering background of Huoluowan Coal Mine, three main factors and treatment techniques for the support crushing disaster of working face under the residual coal pillar are introduced. The dynamic load pressure model of the double key stratus is established, and the periodical pressure behavior of the failure of upper key layer is proposed. The load formula of the working face hydraulic support during the coal pillar is obtained. On the basis of the mechanism analysis of strong pressure on the working face under the residual pillar, the roof cutting and pressure relief scheme was implemented. The average support pressure was reduced by 15%-20% after hydraulic fracturing.