A machine tool includes a spindle including a tool insertion portion having a shape of an opening into which a shank of a tool is inserted and configured to attach the tool thereto, a tool change unit configured to change the tool attached to the spindle while gripping the tool, an air supply unit configured to supply air to a gap between the tool insertion portion and the shank of the tool when the tool change unit changes the tool, and a controller configured to control driving of at least any one of the spindle and the tool change unit to allow the tool and the tool insertion portion to reciprocate relative to each other in a predetermined direction with the shank of the tool inserted into the tool insertion portion and with a gap provided between the tool insertion portion and the shank of the tool.