The influence of the naphthalene superplasticizer, aliphatic superplasticizer and water repellent on the properties of sulphoaluminate cement mortar such as strength and anti permeability was studied by orthogonal test method, and the microstructure of hydration products of hardened mortar was observed by X-Ray and SEM. The results showed that, adding amount of additive in sulphoaluminate cement, can improve mechanical properties of sulphoaluminate cement, and effectively improve waterproof performance and impermeability of mortar. When the water repellent admixture is 0.2%, the naphthalene superplasticizer 0.7%, aliphatic superplasticizer 1%, mortar impermeability is at its best, reaching 1.6MPa.