Abstract: It is the clay minerals that distribute widely in the key gas-bearing reservoirs of the 8th Member of Shihezi Formation and the 1st Member of Shanxi Formation in the Upper Paleozoic of Sulige gas field. The content change of clay minerals influences the pore structure features, initiates the reservoir sensitivity, changes the reservoir seepage ability and affects the gas productivity in Sulige gas field. Through studying the characteristic of clay minerals and reservoir sensitivity, it can be concluded that core permeability is influenced by water-sensitivity, acid-sensitivity, stress-sensitivity, speed-sensitivity, and salt-sensitivity by turn from the strong to the weak. It is the water-sensitivity and acidsensitivity that are the most harmful to reservoir. At the same time, corresponding measures for reservoir protection and reconstruction are proposed. For example, it needs high sand ratio and low fracturing fluid during the course of fracture technology for water-sensitive area. Attention should be paid to acid-sensitive injury to reservoir of chlorite enrichment region. For improved acid-sensitive reservoir, rational prepositioned acid fracturing technique could be adopted to carry out reconstruction, enhance permeability and increase single well productivity

Key words: Sulige gas field, Upper Paleozoic, clay minerals, reservoir sensitivity