The micro friction and wear performance of single crystal gallium oxide at the nanometer scale is analyzed to provide a theoretical basis for the precision grinding of gallium oxide crystals by diamond abrasives. On the G200 Nano Indenter, using the Cube Corner diamond indenter, at the nanometer scale, the friction and wear tests of the (010) and (100) crystal planes of single-crystal gallium oxide are performed, and the morphology after the test is observed using an atomic force microscope and then the size is measured. When the diamond is rubbed against single-crystal gallium oxide at different speeds, the slopes of the straight-line fitting between scratch widths and depths of the (010) and (100) crystal planes and the friction speed are 4.057 69 and 7.634 62, 0.820 73 and 0.798 62, respectively. When rubbing gallium oxide with different loads, the slopes of straight-line fitting between scratch widths and depths of the (010) and (100) crystal planes and the load are 47.625 and 46.750, 23.764 and 31.9546, respectively. The depth of scratches increase from 571.22 nm to 2964.81 nm as the friction number of times increase from 889.34 nm to 7360 nm in repeated friction wear tests. In the dry friction state, the friction velocity of the diamond indenter has little effect on the friction coefficient and wear of gallium oxide. When the load is small, the gallium oxide wear is removed by plastic deformation. When the load increases to a certain value, the wear changes to brittle material removal, and cracks, flaking, and debris appear, which increases the wear. Gallium oxide (100) crystal plane is easier to wear than (010) crystal plane because of its low hardness and easy cleavage.