Abstract: Wellknown trademarks have an absolute significance for sharing market, and any diluting behavior to wellknown trademarks would result in an irreversible damage. There are differences between selfdilution and traditional dilution in terms of their form and subject. In reality, enterprises are alert to the selfdilution of wellknown trademarks, but do not take sufficient care and preventive measures. Exploring the forms, characteristics and preventive measures of selfdilution of wellknown trademarks has vital significance to an enterprises longterm development.

Key words: wellknown trademark, selfdilution, preventive measures