Abstract:The second member of Shuangyang formation in Moliqing fault depression is the main hydrocarbon exploration target in the Yitong basin. Given the low porosity and permeability, we have studied the damage factors of the reservoir in the mining process, and analyzed the susceptibility of the second member of Shuangyang formation which is located in the northwest edge of Moliqing fault depression with the experiments of reservoir flow sensitivity on the basis of understanding the nature of the rock and mineral composition characteristics. The analysis results show that the water sensitivity index of 66.08% on average, with the critical salinity 6 272 mg/L,speed sensitivity index of 37.23% on average, acid sensitivity index of -31.37% on average and the average alkaline sensitivity index of 7.71%. It shows that the reservoir has the strong water sensitivity, moderate-strong salt sensitivity, moderate speed sensitivity, weak alkaline sensitivity and no acid sensitivity. There are many sensitive clay minerals like kaolinite, chlorite, smectite mixed-layer and illite, and the distribution characteristics of these sensitive clay minerals is the most important factor in the mining process. Therefore,when operation is done on the second member of Shuangyang formation of Moliqing oil reservoir, it should prevent speed sensitive and water sensitive firstly. Other sensitive factors should be taken into account to take corresponding measures to protect the reservoir.