Abstract: The updated research on charge characteristics and stability of non-woven polypropylene fabrics was reviewed,and the charge characteristics and stability of non-woven polypropylene fabrics were analyzed in combination with the basic rules of charge storage stability of polymer electrets and the chemical and web structure of non-woven polypropylene fabrics.It points out that the charge storage of non-woven polypropylene fabric electrets mainly comes from the charge trapping at crystallites and interface polarization between crystallites or between crystallites and non-crystallites when current flows through the medium.Suggestion is given as how to improve the charge storage stability of non-woven polypropylene fabrics electrets used as air filter material.