ZrO_2-Al_2O_3 composite oxides were prepared by impregnation method,and La-Ni/ZrO_2-Al_2O_3 catalysts with different La2 O3 contents were prepared by co-impregnation method. The effect of La_2O_3 contents was test for CO methanation and analyzed by BET,XRD and TPR. The results showed that introducing a small amount of La_2O_3( 2% —6%) into Ni/ZrO_2-Al_2O_3 catalyst could increase its methanation activity,especially at low temperature range and high temperature range. Furthermore,the continuous reactions of ...