Copolymerization of propylene and 1,4-divinyl-benzene was successfully performed by a MgCl2-supported TiCl4 catalyst, yielding isotactic poly(propylene) (i-PP) polymers containing a few pendant styrene groups. With a metalation reaction with butyllithium and a hydrochlorination reaction with dry hydrogen chloride, the pendant styrene groups were quantitatively transformed into benzyllithium and 1-chloroethylbenzene groups, respectively, which allowed the synthesis of i-PP-based graft copolymers by living anionic and atom transfer radical (ATRP) polymerization mechanisms.