Copolymerization of styrene with styrene terminated polyisoprene macromonomer (SIPM) by CpTiCl3-methylaluminoxane (MAO) catalyst has been investigated (Cp: cyclopentadienyl). SIPM was prepared by reaction of living polyisoprene initiated with sec-butyllithium (s-BuLi) and p-chloromethylstyrene. The synthesized macromonomer has a high terminal degree of functionalization and a narrow molecular weight distribution. Graft copolymers of polystyrene-graft-polyisoprene have been synthesized with the CpTiCl3-MAO catalyst. The synthesized graft copolymer was confirmed to have a highly syndiotactic sequence on the main chain.