In Tuoputai Area, the upper formations are mainly composed of sand-shale layer and conglomerate sandstone, long segment and high permeability loss easily occurs with unclear loss layer. Based on the evaluation on plugging material compatibility and reasonable gradation, a plugging agent used in drilling was optimized, it is suitable for high permeability loss zone with less influence on the rheological property of drilling fluid, can reduce the amount of API drilling fluid filtration and has bearing capacity of more than 10MPa after sand bed sealing. It is showed in well TP328X that high strength elastic graphite particle composite gel has effective sealing effects in high pressure difference and high permeability leakage conditions and is especially suitable for complex well conditions such as unclear leakage layer, well kicking accompanied with circulation loss and open hole.