The invention provides a behaviour revenue model based collusion group identification method in electronic commerce network, relating to a collusion group identification method in network, with the ultimate aim that collusion of users is analyzed in the scheme to obtain monetary profit. If a collusion group decides to cheat, the cheated object thereof is group external users, so that trade among group member users is more and external trade is less, otherwise group trading profit is reduced and cheating cost is improved. In the invention, similarity method is improved, and the fact that credit obtained by users is concentrated on one user or group while monetary profit is not concentrated on the group is detected, so that whether collusion is existed among electronic commerce users is detected. The invention directly restricts cheating profit and improves cheating cost to restrict collusion. The identification method thereof is more consistent with economics game theory and is more close to substantial cause of formation of collusion group, collusion group in electronic commerce can be effectively identified, and risk in electronic commerce is reduced.