The invention discloses a single-piece packing method for disposable sanitary products. The method comprises a conveying procedure of conveying the sanitary products, a conveying procedure of respectively conveying upper and lower envelopes, a thermal sealing and cutting procedure, a waste absorption procedure and a product discharging procedure. The invention further discloses a single-piece packing device for the disposable sanitary products. The single-piece packing device is provided with a conveying unit for enabling a fore-and-aft clearance of the sanitary products to be consistent, a thermal sealing and cutting combination unit for performing periphery thermal sealing, embossing of easy-to-tear incisions and peripheral cutting in sequence on an upper envelope and a lower envelope on the upper and lower side of each sanitary product, a waste absorption unit for discharging waste edges generated by peripheral cutting, and a product discharging unit. Each sanitary product is clamped between the upper and lower envelopes, and then is subjected to the periphery thermal sealing, the embossing of the easy-to-tear incisions and the peripheral cutting to form a single-piece packed product; the surface of the product is free of folded edges, so that the product looks more beautiful and ingenious; and meanwhile, a gluing machine is eliminated, so that the manufacturing cost is reduced. The single-piece packing device solves the problems of high manufacturing cost, easiness in halt and low packing efficiency of the conventional device, and has the advantages of compact structure, steady operation and high operation rate.