This study aimed to determine the levels of aging anxiety in middle-aged women who exercise and their beliefs about exercise. This is a descriptive cross-sectional study and 221 middle-aged women were contacted. For data collection, a “Personal Information Form”, the “Aging Anxiety Scale for Middle-Aged Women”, and the “Exercise Health Belief Model Scale” were used. It was found that aging anxiety varied according to age, education level, employment status, and the number of years of exercise. It was determined that as women’s general health scores increased, their physical weakness scores decreased. A positive correlation was found between beliefs about the vulnerability of not exercising and the aging anxiety score. The physical weakness score which is a subscale of aging anxiety had a significant effect on the score of beliefs about the vulnerability of not exercising and explained 13.7 % of the total variance. It has been determined that the mental health of middle-aged women is affected by the exercise they perform. It should be provided to make exercise a habit in the lives of middle-aged women and to improve their physical and mental health by organizing exercise programs.