Poly(vinyl acetate) (PVAc) macromonomer was synthesized from the PVAc having a hydroxy group at one end prepared by a free-radical polymerization of vinyl acetate in the presence of 2-mercaptoethanol as a chain transfer agent and methacryloyl chloride. The degrees of polymerization, polydispersity index, and functionality of PVAc macromonomers were evaluated by gel permeation chromatography (g.p.c.) and H-1 nuclear magnetic resonance spectroscopy (H-1 n.m.r.). Copolymerization of the PVAc macromonomers with methyl methacrylate (MMA) and styrene (St) were carried out and traced by g.p.c., suggesting that the polymerization proceeded normally without other side reactions. The resulting polymers were confirmed to be PVAc grafted PMMA and PSt by H-1 n.m.r. and g.p.c. Monomer reactivity ratios between the PVAc macromonomers and the comonomers, MMA and St, were estimated from the copolymerization results. The PVAc branches in the graft copolymer were successfully led to poly(vinyl alcohol) branches by methanolysis.