The utility model discloses a check valve structure with adjustable rigidity, including valve body, baffle and valve membrane piece, the valve membrane piece is for falling umbrella -shaped structure, and the umbrella -shaped structure that wherein falls comprises cylindrical section and umbrella conic section, umbrella conic section sets up inside the valve body, and the cylindrical section is fixed in the centre bore of valve body right -hand member, baffle installation is inboard at the valve body to the right -hand member face of baffle is near the inboard edge of umbrella conic section, the valve body outside is cylindrical structure to be provided with two sealing washers outside on the cylinder, the valve membrane piece adopts silicon rubber materials to make. The utility model discloses a rubber materials's elasticity is utilized to the structure of adjustment rubber valve membrane piece, realizes gaseous uniflow, make an organic whole with the check valve subassembly, the maintainability problem of product can be solved to convenient the dismantlement, and the index of decomposing the pump simultaneously satisfies the sealing load and the cracking pressure requirement of check valve, the uniformity of the input/output index of guaranteeing the pump to the cracking pressure and the sealing load adjustment of check valve through the valve membrane piece.