The soap-free siloxane/acrylate copolymeric emulsion was prepared by using sodium allyl-2-hydroxy propyl ether sulfonate(NaAPS) and poly(hydroxy propionic acid) acrylate(PHPA) as emulsifying system. The influence of types, cooperation and contents of surface-active monomers on the properties of soap-free siloxane/acrylate copolymeric emulsion and its coating were studied. The results show that the coating of the soap-free siloxane/acrylate copolymeric emulsion has better comprehensive properties than that of the general siloxane/acrylate emulsion.