Abstract: First temperature sensors MS are respectively provided on surfaces of a Y-axis moving body, an X-axis moving body, and a U-axis moving body that are machine body components. A second temperature sensor AS is provided on a frame 10F located between a cover 10 and the machine body components. A first estimated temperature is calculated by correcting a detection temperature of the temperature sensor MS with a predetermined first correction coefficient, a second estimated temperature is calculated by correcting a detection temperature of the temperature sensor AS with a predetermined second correction coefficient. The second estimated temperature is added to obtain a synthesis temperature of each machine body component. A thermal displacement amount in a predetermined direction of the machine body is calculated based on the synthesis temperature, and thermal displacement correction in the predetermined direction is performed.