Two new reversible addition-fragmentation transfer (RAFT) agents with 8 and 16 terminal dithiobenzoate groups on the surface of poly(propylene imine) dendrimers (generation 2.0 and 3.0, respectively) were prepared, and successively they were used in the RAFT polymerization to produce well-defined dendrimer-star polymers. The polymerization kinetics were confirmed to pseudo-first-order behavior. The polymerizations displayed excellent molecular weight control and produced polymer with low polydispersities (< 1.3). The synthetic method was also suitable for the preparation of dendrimerstar block copolymers.