A machine tool includes: a spindle that allows a tool to be detachably mounted thereon; a tool changing device that holds a plurality of the tools, and attaches and detaches any of the tools to and from the spindle; a date and time storage unit that stores date and time when operation of the spindle is stopped last; and a calculation unit that calculates unused time of the spindle on the basis of the date and time stored in the date and time storage unit, when the tool is to be detached from the spindle, wherein in a case where the unused time calculated by the calculation unit is longer than a predetermined threshold value, the tool changing device performs detaching motion of the tool from the spindle for longer time compared to a case where the calculated unused time is at or less than the threshold value.