The present invention provides an auction method and system, that is, a seller proposes an expected selling price of an item in a tender offered by the seller and the item is announced and bid on the auction system provided by the manager of auction system, and a end time and a number of bids are set. Many buyers make bids by haggling the price down and a certain tendered bid with every bid is paid, and a bid-winner is a buyer who makes a “lowest price” and “only one” bid when the tender is concluded. The bid-winner is satisfied by buying the item at a low price, the selling price of the item offered by the seller and a commission of the auction system manager are obtained from total tendered bids of total bids and a bidding price by the bid-winner to satisfy three parties, such as the bid-winner, seller and auction system manager.