Background: Self-mastery is an important psychological resource to cope with stressful situations. However, we have limited understanding of self-mastery among minority aging populations. Objective: This study aims to examine the presence and levels of self-mastery among U.S. Chinese older adults. Methods: Data were drawn from the PINE study, a population-based survey of U.S. Chinese older adults in the Greater Chicago area. Guided by a community-based participatory research approach, a total of 3,159 Chinese older adults aged 60 and above were surveyed. A Chinese version of the Self-Mastery Scale was used to assess self-mastery. Results: Out of the 7-item Chinese Self-Mastery Scale, approximately 42.8% to 87.5% of Chinese older adults experienced some degree of self-mastery in their lives. Older adults with no formal education and the oldest-old aged 85 and over had the lowest level of self-mastery in our study. A higher mastery level was associated with being married, having fewer children, better self-reported health status, better quality of life, and positive health changes. Conclusion: Although self-mastery is commonly experienced among the Chinese aging population in the Greater Chicago area, specific subgroups are still vulnerable. Future longitudinal studies are needed to improve the understanding of risk factors and outcomes associated with self-mastery among Chinese older adults.