The invention discloses a pressure stabilizing check valve comprising a main body extending linearly; the main body is provided with a flow channel extending in the same direction as the main body; one end of the main body is provided with an inlet communicating with the flow channel; the side wall of the main body is provided with an outlet communicating with the flow channel; the flow channel is internally provided with a spring and a blocking part; the peripheral surface of the blocking part is hermetically fit to the inner wall of the flow channel; one end of the spring is fixed in the flow channel, and the other end of the spring is used for applying tensile force to the blocking part; the blocking part is provided with blocking positions for blocking a gap between the inlet and the outlet, and communicating positions for communicating with the inlet and the outlet; the blocking positions and the communicating positions are spaced by a preset distance in the extension direction of the main body; and when the pressure difference between the side, close to the inlet, and the side, far away from the inlet, of the blocking part is higher than the elastic force of the spring, the blocking positions move toward the communicating positions. According to the pressure stabilizing check valve, the problem of false opening can be avoided effectively.