In this paper we propose a simple yet robust secure cooperative spectrum sensing scheme with hard decision combining for Opportunistic Spectrum Access(OSA)networks.Based on the historical sensing records and the assistance of trusted OSA nodes,the proposed approach effectively mitigates spectrum sensing data falsification attacks by excluding misbehaving OSA nodes from the process of cooperation.Both analyses and numerical results are provided for various performance metrics,including overall detection probability.Comparison of the proposed method with existing well-known secure spectrum sensing methods verifies the robustness and effectiveness of the proposed scheme. In this paper we propose a simple yet robust secure cooperative spectrum sensing scheme with hard decision combining for Opportunistic Spectrum Access (OSA) networks. Based on the historical sensing records and the assistance of trusted OSA nodes, the proposed approach effectively mitigates spectrum sensing data falsification attacks by excluding misbehaving OSA nodes from the process of cooperation. Both analyzes and numerical results are for performance metrics, including overall detection probability. Comparison of the proposed method with existing well-known secure spectrum sensing methods verifies the robustness and effectiveness of the proposed scheme.