The Internet has become an essential part of our daily life, but excessive Internet use may lead to a number of risks such as Internet addiction. In order to protect teenagers from the risks, it is important to guide them to use the Internet in a safe, responsible, and ethical way. Cyber wellness literacy, as the core issue of digital citizenship, plays a vital role in the physical and mental ... [Show full abstract] well-being of individuals and should be given high priority. While some studies have explored the integration of digital citizenship into school education through digital game-based learning (DGBL), the influence of digital games on teenagers’ learning outcomes, learning motivation, and engagement in the field of cyber wellness remains unclear. It is, therefore, a challenge to provide cyber wellness literacy learning activities that empower students to keep away from Internet addiction and maintain a happy, healthy, and safe digital life. This study addressed the issue of Internet addiction from the perspective of digital citizenship, and designed and implemented a digital game-based course in a middle school. The study then explored the potential impact of DGBL on improving students’ cyber wellness literacy, motivation, and engagement. The statistical results show that DGBL not only promoted the students’ cyber wellness literacy in preventing Internet addiction, but also enhanced their motivations and emotional engagement.