The confined of PEG in PVA-g-PEG graft copolymers was investigated by differential scanning calorimetry. The crystallization kinetics was discussed by several methods. The results showed that the lower temperature peak (Tp) shifted to the lower temperature and its peak intensity also decreased with increasing the cooling rates, t1/2 decreased and G increased. The Tp of graft copolymers were lower than pure PEG and t1/2 of which were higher than pure PEG. The graft ratio had litter influence on t1/2. The results also showed that both Jeziorny method and the new method combing the Avrami equation described this system very well.