With the improving of the communication technology and the increasing of the applications, the wireless spectrum resource becomes more and more scarce. The resources utilization rate of the primary users who has been assigned resources is low. The cognitive radio technology hope to improve spectrum utilization in a way that the second users use the the primary users' resource. Spectrum sensing is a key technology of the cognitive radio. This article is based on the existing sensing technology,and put forward a new sensing mean. In cognitive radio network, the respective signal to noise of second users are not same because that their distance to the first user and their own signal environments are different. The dynamic dual-threshold cooperative spectrum sensing method is an improvement over the traditional two-threshold energy-aware approach. It improve the sensing performance by fully considering the difference between the secondary users.It has several steps. First of all, it need to filter out some second users that do not meet the conditions, such as, the probability of detection and false alarm. Then, each second user will dynamic change its dual-threshold which is used for energy detection according to its SNR. Through comparing with the single threshold energy-aware cooperative spectrum sensing method and the traditional dual-threshold cooperative spectrum sensing method, we can find that our method has a better performance on improving the overall performance of the system than both of other two methods.