In this study, the grinding experiments were conducted on SiC particle-reinforced aluminum matrix (SiCp/Al) composites under wet, dry, cryogenic, and ELID grinding conditions, and the effects of grinding depth and table speed on grinding forces and grinding force ratio were investigated. The experimental results showed that both the normal and tangential grinding forces of SiCp/Al composites increased evidently with the increasing of the grinding depth and table speed under the four grinding conditions. And the grinding forces under the cryogenic condition were the largest, the grinding forces under the dry condition were the second, and the grinding forces under the wet condition were the minimum. Additionally, the grinding force ratio values decreased with the increase of grinding depth under the wet and dry conditions, while the grinding force ratio values increased slightly with the increase of the grinding depth under the cryogenic and ELID grinding conditions. The grinding force ratio was minimum under ELID grinding condition.