With the rapid development of time and technology, the significance of digital game development cannot be underestimated. In today's era, games have permeated thousands of households, encompassing a wide range of genres. They are no longer solely entertainment products but also can be applied in education, medical care, learning, scientific research, and other fields. Research indicates that serious games (games designed to teach knowledge and skills or provide professional training and simulation) can effectively improve mental health. This review discusses the current status and future prospects of serious games in promoting mental health. It presents a comprehensive classification of serious games by integrating several literature resources, synthesizing information and data analysis to investigate their effectiveness in improving mental health outcomes. The findings show that serious games play a certain role in the treatment of mental illness. However, the current body of research is not without limitations, as there exists a dearth of controlled experiments comparing the efficacy of serious games to other types of games and investigating the effectiveness of gamification techniques. To address these gaps, researchers and designers should further prioritize approaches such as emotional design and participatory design. Additionally, leveraging emerging technologies like virtual reality can facilitate the development of adaptable game designs and methodologies that align with evolving societal needs.