Monopolistic competitive market is a normal market which is between fully competitive market and fully monopolistic market, the previous theories about monopolistic and competitive market don’t bring the game of demand and supply or information collection into the research scope.Based on the incomplete information and lasing utility of commodities, and constructing model through the game of demand transactions, this paper analyzes informationgathering of participants, pricing strategies of suppliers, and market equilibrium.Moreover, the model itself and the conclusions drawn from the model will provide theoretical support for exploring optimal strategy between participants and market managers.