Remote monitoring low-pressure-difference check valve is mainly composed of low-pressure-difference check valve and position indicating system. The valve automatically opens under the action of medium and automatically closes when the back pressure is medium pressure, and can reopen when the outlet pressure reduces to a certain value, and can operate with a certain flow maintained under long-term low-pressure-difference condition. When the value opens or closes, the indicating rod installed at the rocker drives the sensor to interact with the external receiver, and the result is transmitted to the control room; no contact is needed between sensor and medium in the whole process. Remote monitoring low-pressure-difference check valve is applied at containment recirculation pipeline connected with gravity injection pipeline in the PXS system (Passive Core Cooling System) and at the outlet of IRWST (In-containment Refueling Water Tank). Under the design basis accident condition (e.g. LOCA), PXS should carry out safe injection to RCS (Reactor Coolant System) to provide sufficient reactor core cooling. When RCS pressure drops, IRWST can carry out injection via the low-pressure-difference check valve at the outlet to long provide core cooling injection for safe shutdown.