This research analyses the relationship between achievement motivation, educational consumption satisfaction, and subjective well-being of Chinese students studying in South Korea. Students exchange their original support system and growth environment for an unfamiliar cultural environment, and must adapt to the new milieu and language, as well as learn a new way of life. Therefore, the problems they face are diversified, and they are more likely to experience more problems than local students. In the process of studying abroad, the most common difficulties faced by international students are academic issues, career development, and stress. In addition, studies have shown that these factors may also affect the physical and mental adaptation of international students. Following the outbreak of the COVID-19 pandemic, international students were detrimentally affected by the prevention and control of the pandemic in various countries, their original lifestyles have been seriously impacted, their anxiety levels have risen, and the degree of subjective wellbeing has declined. Subjective well-being has remained an important research field in positive psychology. Positive psychology discusses subjective well-being from three perspectives: emotional experience, personality traits, and environment. It holds that positive experience, traits and environment can help improve one’s quality of life, enabling people to persist in the face of difficulty, relieve psychological pressure, and reduce the occurrence of psychological disease. Achievement motivation is the intrinsic motivation for individual success. It is the motivation for individuals to pursue what they consider important, to perform valuable work, and to achieve success through the pursuit of high standards. Consumption satisfaction of university education service refers to students’ comprehensive evaluation of school education after reaching psychological or expected goals. The logical relationship between the three is consistent with the research framework of positive psychology. This research yielded the following results following hypothesis testing on sample data of 425 Chinese students studying in South Korea: (1) Achievement motivation has a significantly positive (+) effect on subjective well-being. (2) Achievement motivation has a significantly positive (+) effect on educational consumption satisfaction. (3) Educational consumption satisfaction has a significantly positive (+) influence on subjective well-being. (4) Educational consumption satisfaction has a partial mediating effect on the influence of achievement motivation on subjective well-being. The results show that, firstly, achievement motivation, as the need or trend of pursuing success, represents the desire or tendency to solve and do things as well as possible, and has the directional significance of emotion, cognition and behavior. As an internal driving force, achievement motivation plays an important role in the process of studying abroad. Secondly, in the few studies done on education consumption satisfaction, we found that some foreign scholars and educators have realized the importance of education consumption satisfaction, and gradually carried out research on the concept, measurement, and influencing factors. Our research provides an empirical supplement for this.