Due to the large-scale development of gas wells in Changqing Oilfield, most gas recovery process will produce annulus pressure phenomenon, it has seriously affected the normal operation of the production, and sometimes even forced to stop production to take measures to solve the problem of gas pressure. According to the development of Changqing Oilfield reservoir, studied the toughness cement slurry system, the development of the oil well cement toughness agent G423E1, with the oil well cement additives in conventional distribution according to certain proportion, formed for toughness of Changqing oil field gas storage well cement slurry system formulation. The results show that the formation of the toughness of the cement slurry system mechanics performance, cement tensile strength increased by 39.9%, cementing strength increased by 19.5%, Young’s modulus was reduced by 46.86%, Poisson’s ratio increased by 9.66%. Cement should stress strain curve is very well, the strain of cement stone 1.5%, cement rock body has not yet destroyed, cyclic loading curve of cement stone with good repeatability showed good cement mechanical stability. So as to improve the pipe string tightness and strength of cementation of cement stone and cement job quality, satisfy the demand of gas storage well long period of injection production alternating should stress the integrity of cement stone, and prolonging the service life of gas storage well. The toughness cement slurry system has been tested in X well and has achieved good cementing effect.