In this paper, a method of disassembly time evaluation for a product has been proposed. The product designer can predict the ability of disassembly for a given product in terms of time by considering a type, size, weight, connection parts, and the movement distance of the product. The equation for calculating disassembly time were derived by applying the basis motion status of worker and some informations of connection parts, various tools, and many different type of assembly structures. The developed method of evaluating disassembly time has been applied to disassemble the product by manual labor. The proposed method has shown that the actual disassembly time was well predicted.