The purpose of the paper was to investigate the rough grinding and finish grinding of alumina ceramic using small diameter of diamond tools under high spindle speed. The effect of the grinding conditions on grinding forces and surface roughness was discussed. The three types of experiments were carried out: (1) For rough grinding of alumina, when a metal sintered diamond tool of grit mesh #100 under a lower spindle speed of 10000 rpm was used, the relatively higher grinding ratio of 2452 and the higher material removal efficiency were obtained. Oppositely, for a higher spindle speed of 30000 rpm, the lower grinding ratio of 503 and the lower material removal efficiency were produced. (2) For finish grinding of alumina, when the metal sintered diamond tool of grit mesh #1000 under a higher spindle speed of 50000 rpm and a lower depth of cut of 1 μm was employed, the resulting better surface roughness obtained was Ra 0.33 μm. (3) The pressure grinding of alumina was used to obtain a better surface roughness of Ra 0.23 μm than the high speed fine grinding. Hence, it can be used as an ultra finishing after rough grinding.