Chip control is a major problem to be solved in automated machining system. It involves a total system to produce chips that can be evacuated easily and reliably from the working zone and can be disposed of efficiently. In order to realize those, prediction of chip-breaking in machining is one of effective methods. In this paper, to predict the chip breakage systematically, the equivalent parameters concept is used. Through presenting a study of the effect of complicated groove insert equivalent parameters on chip formation and breaking, a predictive model of chip-breaking is constructed. Finally, chip-breaking experiments are made and the tested results show that differential chip-breaking point’s ratio is fewer than five percent, so it proves that the chip-breaking predictive model is reasonable.