Abstract: Guangxi is a province of aluminum production in China, in the production of aluminum will produce a red mud which would cause pollution. Because the alkaline base of red mud is difficult to remove, groundwater would be polluted. Dumping large amounts of red mud, not only take up large tracts of land, dry red mud can also cause dust pollution. Effectively recycling of red mud has become an urgent task. This study attempts to use aluminium oxide, which is as one of the main components of red mud to mixed with red clay. Researching the physical and mechanical properties of red clay which mix in alumina. This experiment adopts mixed rate respectively of 0, 1%, 2%, and 4%. Using this five mixing ratio of Al2O3. To testing its liquid-plastic limit. Analysis the liquid-plastic limit changes of red clay with different rate of the doped alumina. By compaction test, concluded that the red clay under different mixed rate of maximum dry density and the optimum moisture content. Finally, tri-axial shear test of non-consolidation and non-drainage on the reshape sample of red clay, obtained the variation of the stress-strain curves, elasticity modulus, shear strength parameter in the same moisture content, different mixing rates, under different confining pressures. The experimental results show that the modified red clay with high liquid and plastic limit features, and its status is hard. Along with the addition of aluminum oxide increases, the liquid limit, plastic limit, and plasticity index, moisture content, maximum dry density decreases; with the same alumina mixed quantity of cases, as the confining pressure increases the shear strength increased, under the same confining pressure, with the increase of alumina mixed, shear strength in the low first, then increased.