Abstract: A series of polyethylene glycol/graphene oxide (PEG/GO) hybrid materials were prepared via ultrasound intercalation in an aqueous medium, and the intercalation structure was studied. It was found that the skeletal structure of GO remained the same in the hybrid materials after intercalation. With increasing PEG content, the interlayer spacing of GO and the thickness of the intercalated PEG chains first increased, reached maximum when the saturation content of PEG molecules in the GO layers was 30.17wt%, and then decreased. The intercalated PEG molecules took trans conformation, and the orderly structure of monolayer array of zigzag chains of PEG was proposed to form in the confined GO gallery. FT-IR analysis showed that a remarkable red shift of O-H stretching vibration absorption peak from 3406 cm-1 of GO sample to 3371 cm-1 of PEG/GO hybrid material can be observed, and a strong intermolecular hydrogen bonding formed between the molecules of PEG and GO, resulting in the improvement of the thermal stability of GO. The PEG/GO hybrid material was expected to be applied to enhance the mechanical, tribological and anti-static properties of engineering plastics.