Abstract: Cognitive radio technology has been the research hotspot recently emerged as a novel feasible solution to address the spectrum sharing problem. How to ensure the feasibility and reliability of spectrum resource allocation is the new challenge for cognitive radio technology. A dynamic reputation scheme based spectrum allocation strategy is proposed in this paper. The Vickrey-Clark-Groves mechanism and subject logic theory is used in the strategy to solve the two problems that are strategy-proof and irrational behavior of cognitive users. The strategy can prevent the strategy-proof of rational cognitive users when they apply the spectrum resource on the one hand and on the other hand to effectively control the user’s irrational behavior. And a corresponding algorithm is designed according to the strategy. Finally, the simulation result shows the algorithm can improve the spectrum usage of the system and alleviate influence of the system caused by the user’s irrational behavior.