The film properties of the reactive latexes have been studied on the reactivity of surface functional groups at the interfacial zone of reactive latexes. A series of poly(styrene-co-butylacrylate-co-glycidyl methacrylate(SB-G) latexes having different amount of surface epoxy group were prepared using semi-continuous seeded emulsion polymerization method. Carboxylated poly)styrene-co-butadiene)(SBd) was used as a latex particle containing carboxyl group. Polymer films were prepared by blending above two latexes and drying them. We have invstigated the effect of the blending ratio of two kinds of latexes and the content of epoxy groups of latex particle surface for polymer films. Interfacial crosslinking by chemical bondings between epoxy and carboxyl groups of adjacent polymer latex particles improved barrier properties and mechanical properties. As the blending ratio increased, the crosslinking density, water sorption, and the tensile strength of polymeric films were improved by the increased interfacial crosslinking. As the content of the epoxy group on latex particle surface increased, the crosslinking density increased, which resulted in the increase in tensile strength of polymeric films and the decreased in the permeability of the films.