Abstract: A bidirectional flow control valve functions as a pressure relief valve as to flow in one axial direction and as a check valve as to flow in the other direction, comprising a generally cylindrical casing with a central axial bore in which a poppet having a central head and peripheral flow openings and a cylindrical valve seat member having a central flow passage and an annular valve seat are slidably restrained and spring biased toward each other to seal the valve by engagement of the poppet head and the valve seat, preventing axial flow, the poppet biasing spring exerting a greater force on the poppet than the force exerted on the valve seat member by the valve seat member biasing spring such that the valve serves as a relief valve which opens when fluid pressure on the poppet compresses the poppet biasing spring allowing displacement of the poppet head from he valve seat and as a check valve when fluid pressure on the valve seat member compresses the valve seat member biasing spring allowing displacement of