Polyethylene glycol (PEG) was a kind of thermoplastic polyether polymer with perfect crystal and water solubility. According with requirement of reversible deformation structure of shape memory materials, PEG was widely applied in shape memory polymer material based on the changeable molecular chain structure between amorphous state and crystalline state. The progress in the application of PEG to shape memory polymer, shape memory hydrogel and shape memory composite materials in recent years was reviewed in this paper. The relationship between PEG molecular chain structure, shape memory effect and the response to various stimuli was demonstrated and the importance of hydrogen bonding interaction of polyethylene glycol with water to waterinduced shape memory property was highlighted. Biomedical applications of PEG based shape memory polymer materials with low toxicity and good biocompatibility were also prospected.