Abstract: The presented optimization strategy is intended to be applied to the machining process of complicated workpiece where cutting depth and width may be varied remarkably. By subdividing the whole duration into time spans with comparatively stable machining parameters, the continuous varying parameter optimization problem is transformed to discrete multi-parameter optimization problem and the corresponding model is constructed. Then the multi-parameter optimization problem is rapidly solved by decomposing it to many sub-problems. Finally the results are verified with an example.