Middle Jurassic Toutunhe Formation in Fudong slope is one of the important hydrocarbon objective layers in eastern Junggar Basin. The complex reservoir sensitivity restricted the development of oil and gas. Clay minerals are low in Toutunhe Formation, but the mineral types are rich, and various types of clay minerals are developed. The mixed-layer smectite and illite are most abundant. Through the liquidity experiments, the reservoir has the strongest water sensitivity, followed by salinity sensitivity and acidic sensitivity, which are the main reasons for the reservoir damage. The damage degree of the sensitivities is associated with the types of clay minerals, pore throat and clastic composition. The sensitivity analysis shows the importance of the process of reservoir protection in drilling and testing to reduce formation damage.