Abstract: Effect of emulsifier and it′s content on the film morphology of N--βaminoethyl-γ-aminopropylpolydimethylsiloxane(ASO-1) assembled on silicone wafer was studied by atomic force microscope(AFM).It is discovered that the films assembled from the microemulsion in water are rougher than the films assembled from diltuted amino polysiloxane in ethyl acetate solution,which possibly resulted from some emulsifier participating films formation and residual on the film surface.It is also found that the formation mechanism of the films assembled in microemulsion with different emulsifier content was different,which made the films have different rough morphology.Only by controlling emulsifier/ASO-1=40%(mass ratio) can we obtain flat and smooth hydrophobic film,root mean square roughness of the film in 2μm×2μm scanning field is 0.124 nm and the contact angle is 94.88°.