Sag compensation apparatus of machine tool and machine tool including same

A sag compensation apparatus of a machine tool, the sag compensation apparatus comprising:

• a base unit;
• a housing unit having a hollow portion therein and coupled and installed onto the base unit;
• a cylinder unit installed in the hollow portion and configured to be movable upward or downward;
• a support unit extending while penetrating the cylinder unit and having one side coupled to a bed or a column and the other side coupled to the base unit;
• a flow path unit having one side installed while penetrating a part of the housing unit;
• and
• a compensation unit installed to communicate with the other side of the flow path unit and configured to recover or supply, through the flow path unit, hydraulic pressure between the housing unit and the cylinder unit in accordance with a load of the cylinder unit.