The purpose of the study was to investigate the level of leisure-time physical activity (LTPA) among midlife Korean American women and to determine the relationships of LTPA with individual characteristics and behavior-specific cognition and affects. A cross-sectional descriptive study of 152 middle-aged Korean American women in Central Texas was conducted using a health-promotion model of physical activity adapted from Pender's Health Promotion Model. The results showed that 32% of the participants were not engaged in any form of exercise. The level of acculturation was not significantly related to the amount of physical activity. After age, level of acculturation, education, income, and marital status were controlled, LTPA was significantly associated with perceived benefits and barriers and social support. Physical inactivity, which was common in this group of immigrant women, warrants further rigorous investigation to determine the dynamics of the women's involvement in more physical activity.