<p>A control device of a machine tool 100 has an input unit for inputting the processing profile data 1a and the workpiece data 1b of material and a profile of the workpiece to be processed; a data base 3 for storing at least one of the mechanical data of the machine tool to process the workpiece and the tool data of the tool mounted on the machine tool; an estimating calculation unit 7 for estimating at least a processing load or the occurrence of interference of the tool with the workpiece based on the data inputted by the input unit 1 and the data stored in the data base 3; and a tool path deciding unit 5 for creating a tool path to process the workpiece and deciding a processing condition for processing the workpiece such as a spindle rotating speed and a feed speed of the machine tool 11 based on the result of estimating calculation conducted by the estimating calculation unit 7. <IMAGE></p>
