Abstract：  English auction and Dutch auction of the property were obtained based on the zerosum equation of weighted marginal utility to solve equilibrium price of the property deduced by a pricing model of negotiating transaction of the property right which can maximize wealth value, and by considering the differences between preference and utility function and the differences between the bidding reservation prices and the expected value to the object among different bidders where the preference and utility function of the auctioneer are given and the winning prices in competitive bidding. By comparing the winning price which is the highest equilibrium price in the sense of Pareto optimality, the loss of wealth and inefficiency in two situations were analyzed, one taking the highest value accepted by the bidder as the winning price, the other taking the reservation price of the auctioneer as the winning price. Finally, an economic explanation for the fair transaction maximization of the value of the property right was given.