Abstract:The CSI 300 stock index futures have been listed in China for more than one year.Based on Cointegration theory associated with the arbitrage performance,the arbitrage of the stock index future was investigated.However,it exists a main problem in those studies,i.e.,the information in the latest data couldn’t be revealed effectively if the sample period was fixed.To remedy this limitation,a new Cointegration theory-based EWMA model was proposed in the paper,and a empirical study was conducted by using the real traded data of the CSI 300 stock index futures to demonstrate the effectiveness and efficiency of the proposed model.