||Although poly(vinyl amine)(PVAm) has very simple structure, but it is not easy to prepare PVAm with controlled structure. Since it cannot be polymerized directly from its monomeric form, suitable precursors,such as N-vinyl formamide(VF), need to be polymerized first, and then hydrolyzed. Due to its unconjugated vinylic structure, the reaction of active radicals from VF is too fast to be controlled. Reversible addition fragmentation chain transfer(RAFT) via rapid equilibrium of chain transfer agent(CTA) provides the possibility of giving poly(VF) with controlled structure. In this study, we synthesized a series of PVA-b-PVAm by a sequential RAFT process of vinyl acetate(VAc) and VF, following by hydrolysis reaction. The conversion of monomer and molecular weight of the polymers were measured using GC and GPC, the chemical structures were analyzed with H1-NMR and FT-IR. The kinetic plots of the monomer conversion versus time revealed the controlled characteristics of the polymerization.