Abstract: In this paper, the graft copolymer PP-g-MAH was prepared by polypropylene and maleic anhydride (MAH) by free radical polymerization with the initiator benzoyl peroxide (BPO).The copolymer was characterized by IR,it is showed that copolymer posses more a Carbonyl group of peaks compared with PP. The crystallization morphology was in investigation by polarizing microscope,and the size of crystal was measured.The isothermal and non-isothermal kinetics of copolymer was researched by differential scanning calorimetry (DSC).In the non-isothermal process, the crystallization kinetics was investigated with different cooling rate such as 5, 10, 20, 40℃/min. respectively.In the isothermal process, the crystallization kinetics was investigated with different annealing temperature such as 128, 130,132,134 and 136℃.The DSC dates was discussed by Avrami and Ozawa equation,and the index of crystallization kinetics and crystallization rate constant was obtained .