In this study, two methods to evaluate the disassemblability of the parts are proposed, which are constructed from the concepts of ease-of-disassembly and disassembly time. A method to evaluate the disassemblability of the products is consequently developed using the concept of minimum parts. The methods are applied to evaluate the disassemblability of computer cases. The results show the conclusions that the new model has less disassemblability than the old one. These methods are expected to be used for the evaluation of the possibility of remanufacturing and recycling of a part.