Provided is a keyword advertising system extracting search listings in response to a search request, the system comprising: an interface receiving bid price information corresponding to a keyword from an advertiser; a search information database storing search listings associated with the advertisers in association with each of the received bid price information; a ranking module generating a search result list by referring to the search information database, in response to a search request from a searcher; and a search results providing module providing the searcher with the generated search result list; wherein the ranking module generates the search result list by performing the steps of: identifying a keyword received from the searcher in association with the search request; selecting N of search listings from the at least one search result listing corresponding to the identified keyword, based on the bid price information; and ordering the selected search listings in order of click through rate.