In the past decade, computer games have been gradually seen as one of effective teaching methods and environments, and they have been widely applied in various fields. The purpose of this case study was to investigate the usability of the computer Game, Crazy Machines 2, as a digital game-based learning material through heuristic evaluation to ascertain whether the game conform to interface design principles. Research results indicate that the highest-point indicator is the game interface which provides immediate feedback to solve related missions or problems. The second-highest is game rules which appropriately provide missions or constructive feedback icons to students, enabling them to know what is happening. The lower-point indicator is the social interaction feature, experts consider that if students have different media and the best communication tools, they will achieve the best learning effect. This study recommends future research towards adding the indicators of playfulness and joyfulness into the heuristic evaluation tools.