The invention discloses a system and a method based on Internet auction, relating to the technical field of Internet, the system comprises a homepage module, a registration and login module, a competitive purchase history module, an auction module and a personal center module, the system is used for realizing auction, after the auction is started, all successfully registered auctioneers participate in the auction after paying the deposit corresponding to the product auction price, the price of the auction is increased every time according to the price increase amplitude set by the product, andwhen the auction time is over, the auction is not successful, i.e., flow auction is carried out; when the auction price reaches the highest transaction price before the auction time is over, transaction is performed according to the price, and auction is over; and when the auction is finished and the price is between the lowest transaction price and the highest transaction price, transaction is performed according to the price. By adopting the technical scheme, the method can be effectively combined with the Internet and community marketing to achieve the purpose of facilitating transactions,a lot of intermediate links are saved for achieving the transactions, and a good social network communication effect is achieved.