To cause redundantly provided supply/discharge circuits of hydraulic oil for a ram cylinder to exhibit multiple functions, regarding a hydraulic circuit for the ram cylinder.

The hydraulic circuit for a ram cylinder comprises: a ram cylinder for driving a device to be driven; a control valve hydraulic unit which includes a supply control circuit provided with a supply control valve for controlling hydraulic oil of a hydraulic source and with a supply throttle valve for restricting an amount of oil supplied, and a discharge control circuit provided with a discharge control valve for controlling the hydraulic oil returning from the ram cylinder and a discharge throttle valve for restricting the returning hydraulic oil; a first supply/discharge circuit connecting the ram cylinder to the supply control circuit of the hydraulic unit; and a second supply/discharge circuit connecting the ram cylinder to the discharge control circuit of the hydraulic unit. A downstream side of the supply control valve and the supply throttle valve and a downstream side of the discharge control valve and the discharge throttle valve are connected to each other by a bypass circuit having an opening and closing function, and the bypass circuit makes the first and second supply/discharge circuits exhibit multiple functions.