Nowadays, gaming has grown rapidly into one of the things that exist in everyday human life. Starting from the previous game which is only a means of solace, now has become a means with many other functions, for example, learning and business objects. Changing times and technology has also pushed the development of games in the world to increase rapidly. Games industry and business development is no longer a rare thing, but is now becoming a promising business potential. Unfortunately, not all things only have positive sides. Game is something that gives fun but also has an addictive tendency that if played inappropriately, can have effects on health, whether bad or not. This study aims to evaluate the ergonomics side of game related to the user interface design and monitor screen. Evaluation is done by providing a task scenario in the game that needs to be solved with a case study on computer gaming. The methods used include performance metrics, Game Experience Questionnaire (GEQ), NASA TLX questionnaires, Questionnaire for User Interface Satisfaction (QUIS), and eye tracking. The results show a more ergonomics design and appropriate monitor screen used of some assessment components. In addition, design recommendations were also made which are expected to improve the ergonomics side of a computer gaming.