The effects of different valence inorganic salts on the performance of sodium petroleum sulfonate (NPS) emulsion were investigated by observing the apparent viscosity, interfacial tension and dehydration rate of crude oil emulsion. The results show that NaCl and KCl can be enhanced the action of NPS in a certain concentration range. When the concentration of NaCl and KCl are 9 mmol/L and 12 mmol/L, NaCl and KCl can increase the apparent viscosity of emulsion by 224.03 mPa•s and 122.48 mPa•s, the interfacial tension can decrease by 10.6 mN/m and 9.6 mN/m, and the dehydration rate can reduce by 10.7% and 8.2%, respectively. As the concentration of inorganic salts MgCl2 and CaCl2 increases, MgCl2 and CaCl2 can decrease the apparent viscosity and increase the dehydration rate of NPS emulsion, while the interfacial tension decreases first and then increases.