This study aimed to identify factors that influence self-management behaviors in older people with multiple chronic conditions based on the Individual and Family Self-Management Theory. Methods: Data were collected in metropolitan cities B and Y in South Korea from September 2 to October 4, 2023. A total of 149 older people with multiple chronic conditions completed a structured questionnaire. Data were analyzed using descriptive statistics, independent t-test, one-way analysis of variance, and stepwise multiple regression analysis. Results: The mean age of the subjects was 73.9±7.3 years, and 65.8% were women. As a result of stepwise multiple regression analysis, the factors influencing self-management behavior were family functioning (β=.32, p<.001), self efficacy (β=.24, p<.001), subjective economic status (β=.15, p<.05), duration of chronic disease (β=-.14, p<.012). This regression model was explained by 56% of the self-management behaviors. Conclusion: The findings suggest that continuous and comprehensive approaches to improving family functioning, increasing individual confidence in health care, and addressing economic barriers lead to more effective management of chronic conditions.