A die cushion device comprising: a hydraulic cylinder adapted to vertically move a cushion pad; a first hydraulic pump adapted to supply hydraulic oil from an oil tank to the hydraulic cylinder; a relief valve adapted to return hydraulic oil discharged from the hydraulic cylinder, to the oil tank; a check valve that is arranged, on the flow path between the hydraulic cylinder and the first hydraulic pump, on the first hydraulic pump side from a connection point at which the relief valve is connected to the flow path, the check valve being adapted to regulate a flow of hydraulic oil from the hydraulic cylinder to the first hydraulic pump; a pressure sensor adapted to detect a hydraulic oil pressure in a flow path between the hydraulic cylinder and the first hydraulic pump; and a control device adapted to controls a number of rotations of the first hydraulic pump in accordance with the hydraulic oil pressure detected by the pressure sensor, wherein the control device is adapted to reversely rotate the first hydraulic pump when the hydraulic oil pressure detected by the pressure sensor is equal to or higher than a predetermined pressure value the relief valve has a vent port connected to a discharge side of the first hydraulic pump, the pressure sensor is adapted to detects a hydraulic oil pressure, the hydraulic oil pressure being a die cushion pressure of the hydraulic cylinder, and the control device is adapted to control a set pressure of the relief valve with a pressure of hydraulic oil discharged from the first hydraulic pump, control a flow rate and a pressure of hydraulic oil supplied from the first hydraulic pump to the hydraulic cylinder, by controlling the number of rotations of the first hydraulic pump in accordance with the hydraulic oil pressure detected by the pressure sensor, control the number of rotations of the first hydraulic pump to cause the hydraulic oil pressure detected by the pressure sensor to reach a die cushion pressure command value, and reversely rotate the first hydraulic pump to open the relief valve when a hydraulic oil pressure detected by the pressure sensor is equal to or higher than the set pressure of the relief valve. a hydraulic cylinder adapted to vertically move a cushion pad; a first hydraulic pump adapted to supply hydraulic oil from an oil tank to the hydraulic cylinder; a relief valve adapted to return hydraulic oil discharged from the hydraulic cylinder, to the oil tank; a check valve that is arranged, on the flow path between the hydraulic cylinder and the first hydraulic pump, on the first hydraulic pump side from a connection point at which the relief valve is connected to the flow path, the check valve being adapted to regulate a flow of hydraulic oil from the hydraulic cylinder to the first hydraulic pump; a pressure sensor adapted to detect a hydraulic oil pressure in a flow path between the hydraulic cylinder and the first hydraulic pump; and a control device adapted to controls a number of rotations of the first hydraulic pump in accordance with the hydraulic oil pressure detected by the pressure sensor, wherein the control device is adapted to reversely rotate the first hydraulic pump when the hydraulic oil pressure detected by the pressure sensor is equal to or higher than a predetermined pressure value the relief valve has a vent port connected to a discharge side of the first hydraulic pump, the pressure sensor is adapted to detects a hydraulic oil pressure, the hydraulic oil pressure being a die cushion pressure of the hydraulic cylinder, and the control device is adapted to control a set pressure of the relief valve with a pressure of hydraulic oil discharged from the first hydraulic pump, control a flow rate and a pressure of hydraulic oil supplied from the first hydraulic pump to the hydraulic cylinder, by controlling the number of rotations of the first hydraulic pump in accordance with the hydraulic oil pressure detected by the pressure sensor, control the number of rotations of the first hydraulic pump to cause the hydraulic oil pressure detected by the pressure sensor to reach a die cushion pressure command value, and reversely rotate the first hydraulic pump to open the relief valve when a hydraulic oil pressure detected by the pressure sensor is equal to or higher than the set pressure of the relief valve. control a set pressure of the relief valve with a pressure of hydraulic oil discharged from the first hydraulic pump, control a flow rate and a pressure of hydraulic oil supplied from the first hydraulic pump to the hydraulic cylinder, by controlling the number of rotations of the first hydraulic pump in accordance with the hydraulic oil pressure detected by the pressure sensor, control the number of rotations of the first hydraulic pump to cause the hydraulic oil pressure detected by the pressure sensor to reach a die cushion pressure command value, and reversely rotate the first hydraulic pump to open the relief valve when a hydraulic oil pressure detected by the pressure sensor is equal to or higher than the set pressure of the relief valve.