The invention relates to the technical field of lead-acid storage batteries, in particular to a storage battery cover plate sealing method. The method comprises the following steps: 1, reserving a groove in a battery cover, and calculating the length of the inner wall of the groove; 2, designing an O-shaped sealing ring matched with the groove according to the length of the inner wall of the groove; and 3, placing the O-shaped sealing ring in the groove, buckling the battery cover plate into the groove, and respectively extruding the O-shaped sealing ring through the battery cover plate and the battery cover to finish sealing. A more reliable sealing mode convenient to operate is provided. The problems that an existing epoxy resin sealant is long in curing time, secondary sealing cannot beachieved, and the production cost is increased are solved.