The invention discloses a performance recovery heat treatment method for a spherical crown of a composite steel plate. The method comprises the following steps of: 1) quenching, namely heating along with a furnace to the temperature of between 400 and 415 DEG C, stabilizing for a certain period of time, heating to the temperature of between 940 and 960 DEG C at the temperature rise rate of less than or equal to 180 DEG C/hour, discharging and water-cooling to room temperature after heat is preserved for a certain period of time; and 2) tempering, namely heating along with the furnace to the temperature of between 335 and 365 DEG C, preserving the heat for a certain period of time, heating to the temperature of between 660 and 680 DEG C at the temperature rise rate of less than or equal to100 DEG C/hour, discharging and air-cooling after the heat is preserved for a certain period of time. By the performance recovery heat treatment method for the spherical crown of the composite steel plate, the original mechanical property and physical property of the composite steel plate can be effectively recovered to states before hot pressing, so that the performance requirements of high strength and corrosion resistance in nuclear island equipment are met.