Polyethylene glycols (PEG) can dissolve a lot of organic compounds and metallic complexes. Moreover, they are thermally stable, nonvolatile, non-toxic, biodegradable, inexpensive and recyclable. Thus, PEG as green medium has been successfully employed in many organic reactions, such as carbon-carbon coupling reaction, carbon-hetero coupling reaction, multicomponent reaction, condensation reaction, addition reaction, substitution reaction, oxidation reaction, reductive reaction, and so on. The recent advances of PEG applied in orgainc synthesis are reviewed.