Environmental protection has been a critical issue in recent years and many countries have set regulations in regarding to product manufacturing and packaging. From the design point of view, how to minimize the overall impacts to the environment across the entire product life cycle has been the major theme for the industrial designers. The methodology of this study is to review literature about green design. Some guidelines, related to green design principles, material selection, production and mechanical design, have been drawn to provide industrial designers as references when they are undertaken green design practices. A case study on computer Ethernet hub design, applying green design principles, is discussed. And the final design shows great improvements on product structures, the utlise of recycling material, assembly and disassembly procesures.