Many of the applied methods and measurement tools of emotional usability engineering have been recommended for use designing products. A rough set method can also be a useful tool to be integrated with the basic concepts of emotional usability engineering. If such a method is applied, the groups of sensory words have to be investigated and their values reduced and classified to provide comprehensive information to product designers. However, a computational problem exists regarding the number of samples, groups of sensory words, and values required when resolving sense-based minimal decision rules. Considering this problem, we discuss the use of DNA computing, and propose a bio-inspired evolutionary method based on the rough set method, which should provide a new tool for emotional usability engineering.