The present invention provides a uniform resource locator (URL) de-duplication method and device. The URL de-duplication method comprises presetting a de-duplication rule base according to structures of URLs; acquiring URL data to be de-duplicated from website visiting data; matching the URLs to be de-duplicated with de-duplication rules in the de-duplication rule base according to the structures and segmentation parameters of the URLs; and filtering the matched URLs corresponding to the same de-duplication rules, and reserving one URL corresponding to each de-duplication rule. Through the method and device, a massive amount URL data is filtered and de-duplicated through the de-duplication rules, and the situation of repeatedly scanning the same common gateway interface (CGI) by a security flaw scanner during URL security flaw detection is avoided, thereby raising a security flaw detection efficiency.