High carbon CoCrMo alloy has been widely used in orthopedic implants. Carbides improve the strength of the material and influence wear resistance. An atomic force microscopy (AFM)-based single asperity tribology method was developed to investigate the wear performance of individual carbides and base metal matrix of high carbon CoCrMo alloy. Sub-nano to nanoscale wear on single carbides was performed and quantified. Nanowear behavior of two types (Cr-rich and Mo-Rich) of carbides was stress-dependent (from 7.8 GPa to 9.8 GPa) and influenced by chemical composition. The lower wear depth of both Cr-rich and Mo-rich carbide compared to the matrix alloy shows higher wear resistance compared to metal matrix. Cr-rich carbides exhibit significantly smaller wear depth (p < 0.05) compared to Mo-rich carbides after nanowear at the same contact stress (9.8 GPa). The entire region of Cr-rich carbide shows high wear resistance without fracture after nanowear at 14.7 GPa. The AFM-based nanowear methods used are able to detect sub-nanometer wear depths on worn regions as small as 0.2 μm and provide abilities to study local nanometer wear processes in complex alloy systems.