Grafting of maleic anhydride was carried out to the low molecular weight polypropylene in the bulk polymerization condition. As the reaction temperature decreased and the reaction time increased, the graft yield increased. And the bulk polymerization showed a higher graft yield than the solution polymerization did. These conditions seemed to make grafting relatively feasible compared with the side reactions such as chain-transfer and homopolymerization. The melting point of the grafted PP decreased possibly due to the disturbance in compact packing of main chain.