Abstract: This paper provides a model for choosing excellent sellers，using buyer agents standing for buyers and seller agents standing for sellers.With the model，the buyer agent can learn to identify trustworthy buyer agent friends，and combining the information from them and the its own experience，it can identify high quality，low priced sellers in the complex electronic markets.We conduct experiments to confirm that the proposed model is able to accurately identify the trustworthy buyer friends and can choose the excellent seller in the complex electronic markets.Besides，this paper also shows that the agent with this model has higher gain than that with buyer agent acting alone.