Abstract: The preparation conditons of new coating of papers as plastic of biodegradation by copolymerization emulsion with starch as material and styrene as a grafter were studied.Emulsion coating was produced at normal pressure,60℃,starch-styrene ratio of 1∶1, stirring speed of 2000 r/min, 8 hours and through modifying by modifier of synthetic.The results obtained shows that its property is stable, adhesive force on paper is high and property of water-proof is good.