According to the collapsing and leakage in some individual borehole of Shengjingzi oil shale mining area in Jilin, taking PVA as main material, the flush fluid was prepared with better cementation and inhibition properties for collapsing prevention and wall protection. Economical and practical inert materials such as sawdust and peanut shell were used for leakage stoppage to lower the accident rate and drilling cost as well as improving the drilling efficiency.