Abstract: The High water sensitivity reservioir is that the permeability declines exceed 70% when outside liquid enters formation.The development of this type reservioirs is always not good for difficulties to supply the energy by injection water or steam caused by permeability declining dramatically.In present the sensitivity mechanism of formation are applied gradually from experiment to oil field and a set systemic experiment investigation methods about sensitivity formation are formed,but the successful development of the sensitivity reservoirs don't get breakthrough for the formation damage of clay mineral.In this paper Wangzhuang oil field is used as a case of high water sensitivity reservoir to investigate the damage of clay mineral.