Provided are a cognitive radio (CR) cooperative spectrum sensing method and a fusion center (FC) performing CR cooperative spectrum sensing. The CR cooperative spectrum sensing method includes receiving, at an FC, local spectrum sensing information about a predetermined frequency band from each of N secondary users (SUs) in a predetermined zone, determining, at the FC, the optimum number of SUs for determining whether the predetermined frequency band is being used by a primary user (PU) on the basis of the received local spectrum sensing information, and performing cooperative spectrum sensing on the basis of local spectrum sensing information received from the optimum number of SUs in the predetermined zone. The method is implemented by the FC. Accordingly, the method and FC find how many SUs are needed to determine that a frequency of a PU is being used in a corresponding-channel situation, thereby enabling efficient communication.