The utility model discloses a matching structure for a valve seat and a valve sheet of a plate valve. The matching structure comprises a cylinder body (1), the valve seat (2), the valve sheet (3) and a spring (4), wherein the valve seat (2) is fixedly arranged in the cylinder body (1); a water inlet and a water outlet are formed in the valve seat (2); the valve sheet (3) is pressed against the inlet of the valve seat (2) under the action of the spring (4); and an annular rib (9) is arranged on the end face, which contacts with a central valve plate (7) of the valve sheet (3), of the valve seat (2), and has a semicircular section. The matching structure has the beneficial effects that the annular rib is arranged at the bottom of the valve seat, and has the semicircular section, so that the valve seat forms linear seal with the valve sheet, the influence of impurities in a working medium is avoided, and the matching structure is high in sealing performance, stable in working state, high in accuracy, long in service life and low in opening or closing noise; and a sealing mode is changed from an original narrow surface sealing mode into a linear surface sealing mode, and the linear surface sealing mode is more reliable than the narrow surface sealing mode under the condition of same machining accuracy.