In view of the insufficient durability of ordinary mortar in practical engineering application,the durability modification effect of VAE emulsion powder on cement mortar was studied.For VAE latex powder modified mortar with different polymer content (8%, 9%, 10%, 11% and 12%),through shrinkage,cracking sensitivity,impermeability,chloride corrosion resistance and carbonation experiments,the shrinkage,total weight of cracking,water seepage height,water permeability pressure,carbonation depth and chloride ion penetration height were tested.Combined with SEM experiments,the micro modification mechanism of VAE emulsion powder on mortar is revealed.The results show that the addition of VAE emulsion powder significantly improves the impermeability of mortar.When the polymer content is 12%,the total cracking weight of VAE latex powder mortar is only 55.1% of that of ordinary cement mortar,the permeability pressure is 78.6% higher than that of ordinary cement mortar,and the 28 day carbonation depth and chloride ion penetration height are 36.8% and 53.1% lower than that of ordinary cement mortar respectively.VAE emulsion powder and the aggregate in the mortar form a network membrane structure with high adhesion inside the slurry,fill the pores of the modified mortar,make the interior of the slurry more dense,and then enhance the durability of the modified mortar.