The chip decohesion phenomena during micromilling process constitute currently the up-to-date problems in precision manufacturing science. Nevertheless, the role of tool microgeometry in terms of machined surface finish formation and force distribution on the active cutting edge still require intensive research. Therefore, this paper is focused on the evaluation of micromilling tool’s cutting edge radius variations in terms of selected process effects. As part of study, the micromilling tools diversified in terms of geometry (end mills and ball end mills) were inspected on the Alicona microscope. As a consequence, the cutting edge radius values along the cutting edge were obtained. In the next step the theoretical values of minimum uncut chip thickness, surface roughness height and ploughing forces for the end mills and ball end mills were calculated on the basis of analytical models including the effect of cutting edge radius. The conducted analyzes demonstrate that analytical relationships between the cutting edge radius and the machined surface roughness heights (calculated based on a model including minimum uncut chip thickness), as well as the theoretical ploughing forces (determined on the basis of mechanistic model concerning ploughing volume) can be found. Depending on the measured cutting edge radius of the tested micromilling tools, and for the same micromilling inputs, a differences in theoretical surface roughness heights were up to 420%. However, in case of calculated ploughing forces a differences of force values reached up to 55%.