This paper describes the performance of one-bit hard combination scheme of cooperative spectrum sensing for different number of cognitive radio users. We evaluate cooperative spectrum sensing by simulating OR rule as a hard combination data fusion rule. Energy detector is used to observe the presence of primary user (PU) signal. It improves the probability of detection by collaborating to detect PUs signal in cognitive radio (CR) system. Simulation result shows that the probability of missed detection is decreasing for both conventional hard combination and 1-bit hard combination scheme with OR rule correspondingly with increasing the probability of false alarm. It is shown that 1-bit scheme has much better performance than the conventional hard combination scheme. This is also shown that the probability of missed detection is decreased even though CR user is increased. Here missed detection probability is decreased when the number of user increases.