Abstract: An adaptive control apparatus is provided with a load detector for detecting a load which acts on a cutting tool during a machining operation of a workpiece and plural storage areas for one cutting tool which respectively store plural data groups of load values which are sampled during respective model machining operations. In an adaptive control machining operation, a microprocessor selects one of the plural storage areas when receiving tool code data that a numerical controller reads out in accordance with a numerical control program. In the adaptive control machining operation controlled by the numerical controller in accordance with the numerical control program, the microprocessor modulates the feed rate override of the numerical controller so that the feed rate of the cutting tool is varied to make the actual machining load detected during the adaptive control machining operation follow the sampled load values which are successively read out from the selected one of the storage areas.