In cognitive radio networks,Secondary Users (SUs) have opportunities to access the spectrum channel when primary user would not use it,which will enhance the resource utilization.In order to avoid interference to primary users,it is very important and essential for SUs to sense the idle spectrum channels,but also it is very hard to detect all the channels in a short time due to the hardware restriction.This paper proposes a novel spectrum prediction scheme based on Support Vector Machines ( SVM),to save the time and energy consumed by spectrum sensing via predicting the channels state before detecting.Besides,spectrum utilization is further improved by using the cooperative mechanism,in which SUs could share spectrum channels history state information and prediction results with neighbor nodes.The simulation results show that the algorithm has high prediction accuracy under the condition of small training sample case,and can obviously reduce the detecting energy,which also leads to the improvement of spectrum utilization.