The present invention discloses a large-flow plunger pump, comprising a box, a crank-link mechanism, a plunger, a suction valve and a discharge valve. On the basis of the conventional multi-cylinder plunger pumps, assemblies such as a detachable upper crosshead guide, an intelligent plunger packing lubrication system, a damping valve, crankshaft support roller assemblies, and a suction-pressure stabilizer having a cooling water coil therein are invented. Both the service life and the reliability of the large-flow plunger pumps are overall improved.