A serious of hydroxyl silicone oil modified sulfonated waterborne polyurethane was synthesized with sulfonated polyester diols (BY3301), toluene diisocyanate (TDI) as the main raw materials, hydroxyl silicone oil as the modifier and with trimethylol propane(TMP) as the crosslinking agent. The structure and properties of the obtained polymer were characterized by FTIR and TG,digital display viscosity meter,nanoparticle size analyser, etc. And the effects of hydroxy silicone oil content on the properties of emulsion and film were investigated. The results show that with the increase of content of hydroxy silicone oil, the properties of polymer had been improved obviously.the particle size of the emulsion increases and the viscosity decreases, the water contact angle increases, and water absorption of film decreases. The tensile strength of the film gradually increases, and the elongation at break increases. When hydroxyl silicone oil content is 3%, the film has the best comprehensive performance. At the same time, the emulsion particle size is 85.1 nm, viscosity is 114.5 mPa•s, water contact angle is 91.7°, the tensile strength is 14.78MPa, the elongation at break is 427%, water absorption of 24 h is 5.61%. The TG curve shows that when the loss of film quality is 5%, the corresponding temperature is 269.9 ℃, increased by 17.3 ℃ compared with unmodified.