With the proliferation of retail commerce on the Internet, mobile agents play more and more important roles in automating information brokering and negoiation for online shopping. However, due to the limited computing resources and security concerns, current first-generation shopping agents have limited capacities to conduct commercial bargaining. On the other hand, though auctions appear promising to solve these dificulties with their fairness and openness features, they suffer from the problems such as reversed consumer-buyer relation and low performance. In this paper, we propose a secure agent-mediated auction-like negotiation protocol which combines togather the favorable features of traditional English auction and mobile agent scheme. Its features lie at: (1) auctionlike scheme is implemented which keeps the dominant equilibrium in the English auction and rationalizes consumer-seller relation in the retail commerce. (2) security for negotiation agents is guaranteed which makes tampering on agent body easy to detect. (3) flexibility during the trading is achieved by combining information gathering and negotiation together while few communications are needed.