Abstract: The readability research of the package leaflet can improve its quality, make readers understand information in it and ensure its safety to patients. The readability research can also help marketing authorisation holders to design a better package leaflet. So the article takes legal system of the readability of European Union package leaflet as the object, Collate and analyze the readability guideline of package leaflet, look forward to promoting our pharmaceutical research and development.

Key words: package leaflet, readability research, European Union