Abstract: A series of dendritic tri block copolymers with same molecule weight (Mw) and different generations (G) or different molecule weights and same generation were synthesized from PEG10000. DSC was performed to analyse the melting point and crystallization of copolymers. The results showed that with the same Mw, the melting point and crystallization temperature reduced upon increasing the generation, while increased upon increasing Mw with the same generation (G=2). XRD was employed to analyse the crystallization of different blocks. The results showed that with the same Mw, generation influenced the PEG crystallization tremendously and the PEG crystallization was inhibited completely when G≥3. With the same generation (G=2), the polymerization degree (Pd) of PCL arms inhibited the PEG crystallization obviously. When Pd≥22，PEG crystallization was inhibited completely.