PURPOSE: To obtain the durability and the responsiveness by curving a self- curling thermoplastic resin sheet reinforced by reinforcing fibers so as to form a valve plate for a reed valve.

CONSTITUTION: A valve plate in a reed valve used for an intake and exhaust system of a two-cycle engine is formed by curving a self-curling thermo-plastic resin sheet reinforced by reinforcing fibers, the degree of curling of this self- curling resin sheet is set in a range of 0.5 to 6mm, which is the degree of the float-up of one end part thereof. Further, during the manufacture of the valve plate, the self-curling thermoplastic resin sheet contains therein a plurality of fiber-reinforced layers which are laid in parallel with each other. Angles of the orientations of the fibers in the uppermost and lowermost layers are set to be different from each other by 90deg. Then, thus formed self-curling thermoplastic resin sheet is former into a reed valve shape so as to obtain a desired valve plate.