We have introduced macropores that help improve mass transfer of fuel cell electrode by using simple mechanical method. Polymers generally have elastic and inelastic regions when strain is applied. Nafion^®, which is commonly used as a proton conductive membrane for polymer electrolyte membrane fuel cell (PEMFC), has a relatively large inelastic region compared to the elastic region. When an electrode is applied to Nafion^® membrane and strain of inelastic region is applied, the macropores are formed due to the difference in elastic modulus between the membrane and the electrode. The electrochemical performance of MEAs with macropores at various strain ratios was evaluated. We have discussed the cause of performance improvement and durability was also confirmed. Furthermore, research into MEAs that contain shape-controlled macropores is being studied as a replacement for randomly formed macropores.