Abstract: The core sensitivity evaluation in Yonghe natural gas exploration area of Shaanxi indicated that there exists strong water sensitivity in reservoir. The average rate of core damage is up to 61.6% by pre-liquid system. In order to prevent the reservoir core damage by the pre-liquid system, an efficient clay stabilizer NT-2 was prepared. The performances of anti-swelling, anti-immersing and anti-eroding of the clay stabilizer were evaluated by contrast. The results show that these performances are excellent, and the rheological behavior of the fracturing fluid system is not affected by the clay stabilizer, the damage rate of reservoir core by fracturing fluid is reduced. After application of the clay stabilizer on the spot, the production of gas is increased by 3.4 times.