In order to improve the wear resistance, a kind of alumina ceramic with good wear resistance was created in an Al_2O_3-CaC_O3-SiO_2-MgO-La_2O_3(ACSML) system. The effects of La_2O_3 content on sintering temperature, bulk density, and wear rate were investigated. The wear rate of sample was as low as 0.0393‰. The wear resistance of the sample containing La_2O_3 has improved 43% than that of the sample without La_2O_3. Appropriate La_2O_3 doping could inhibit grain growth, enhance density, and purify grain boundary. La_2O_3 could diffuse into Al_2O_3 to form a solid solution and react with Al_2O_3 to form high-aluminum low-lanthanum complex oxides. The combination among Al_2O_3, the solid solution layer, and the layer of high-aluminum low-lanthanum complex oxides combined closely, which could improve grain boundary cohesion. Besides, the homogeneous distributions of elements made uniform structure. Finally, the wear resistance of alumina ceramic was improved.