Theoretical analyses for grinding mechanism have been performed almost in grinding process with constant depth of cut and not so in grinding process with constant load. In this paper, theoretical considerations for grinding mechanism in grinding process with constant load are performed by statistical method. Namely, the rate of effective cutting edges, the distribution of grain depth of cut, grain cutting half width, grain cutting area and load assigned area of grain, and the roughness of ground surface in grinding process with constant load are analyzed theoretically. Further, the results of analyses obtained in this paper are available for honing, superfinishing and belt grinding process successfully.