Cognitive Radio(CR) is a promising technology to solve the challenging spectrum scarcity problem.However, to implement CR, spectrum sensing is the groundwork and the precondition.In this paper, a collaborative spectrum sensing scheme using fuzzy comprehensive evaluation is proposed.The final sensing decision of the proposed scheme is based on the combination of distributed sensing results of different Secondary Users(SUs).To improve the reliability of the sensing decision, the combination procedure takes into account the credibility of each SU, which is evaluated using fuzzy comprehensive evaluation.The effect of the presence of malicious SUs and malfunctioning SUs on the performance of the proposed scheme is also investigated.The efficiency of the scheme is validated through analysis and simulation. Cognitive Radio (CR) is a promising technology to solve the challenging spectrum scarcity problem. However, to implement CR, spectrum sensing is the groundwork and the precondition. In this paper, a collaborative spectrum sensing scheme using fuzzy comprehensive evaluation is proposed. Final sensing decision of the proposed scheme is based on the combination of distributed sensing results of different Secondary Users (SUs) .To improve the reliability of the sensing decision, the combination procedure takes into account the credibility of each SU, which is evaluated using fuzzy comprehensive evaluation. the effect of the presence of malicious SUs and malfunctioning SUs on the performance of the proposed scheme is also investigated. the efficiency of the scheme is validated through analysis and simulation.