A hydraulic unit comprising: a hydraulic circuit fluidly connectable to a hydraulic actuator ; and a control device configured to control the hydraulic circuit , the hydraulic circuit including: a hydraulic oil tank configured to store hydraulic oil; a hydraulic pump configured to supply the hydraulic oil to the hydraulic actuator from the hydraulic oil tank ; a discharge flow path fluidly connected to a discharge side of the hydraulic pump and connectable to the hydraulic actuator ; a valve configured to block a flow of the hydraulic oil in the discharge flow path ; a pressure sensor configured to detect a pressure of the hydraulic oil in a flow path portion , between the valve and the hydraulic pump , of the discharge flow path , wherein when a rotational frequency of the hydraulic pump exceeds a predetermined first determination rotational frequency (N1) or when a discharge flow rate of the hydraulic pump exceeds a predetermined first determination discharge flow rate (Ql), in a pressure holding state in which the hydraulic pump is controlled such that the pressure detected by the pressure sensor is held at a predetermined pressure while the valve is blocking the flow of the hydraulic oil, the control device determines that the hydraulic circuit is abnormal. a hydraulic circuit fluidly connectable to a hydraulic actuator ; and a control device configured to control the hydraulic circuit , the hydraulic circuit including: a hydraulic oil tank configured to store hydraulic oil; a hydraulic pump configured to supply the hydraulic oil to the hydraulic actuator from the hydraulic oil tank ; a discharge flow path fluidly connected to a discharge side of the hydraulic pump and connectable to the hydraulic actuator ; a valve configured to block a flow of the hydraulic oil in the discharge flow path ; a pressure sensor configured to detect a pressure of the hydraulic oil in a flow path portion , between the valve and the hydraulic pump , of the discharge flow path , wherein when a rotational frequency of the hydraulic pump exceeds a predetermined first determination rotational frequency (N1) or when a discharge flow rate of the hydraulic pump exceeds a predetermined first determination discharge flow rate (Ql), in a pressure holding state in which the hydraulic pump is controlled such that the pressure detected by the pressure sensor is held at a predetermined pressure while the valve is blocking the flow of the hydraulic oil, the control device determines that the hydraulic circuit is abnormal. a hydraulic oil tank configured to store hydraulic oil; a hydraulic pump configured to supply the hydraulic oil to the hydraulic actuator from the hydraulic oil tank ; a discharge flow path fluidly connected to a discharge side of the hydraulic pump and connectable to the hydraulic actuator ; a valve configured to block a flow of the hydraulic oil in the discharge flow path ; a pressure sensor configured to detect a pressure of the hydraulic oil in a flow path portion , between the valve and the hydraulic pump , of the discharge flow path , wherein when a rotational frequency of the hydraulic pump exceeds a predetermined first determination rotational frequency (N1) or when a discharge flow rate of the hydraulic pump exceeds a predetermined first determination discharge flow rate (Ql), in a pressure holding state in which the hydraulic pump is controlled such that the pressure detected by the pressure sensor is held at a predetermined pressure while the valve is blocking the flow of the hydraulic oil, the control device determines that the hydraulic circuit is abnormal. <EOS>