The present study performed a cross-sectional survey to investigate sleep habits and sleep health in Japanese women aged 40 to 69 years with and without a habit of exercise. A standardized questionnaire evaluating sleep was administered to two subject groups. One was the “exercise group” who habitually performed aerobic exercise at mild to moderate intensity with a frequency of ≥2 times/week and duration of ≥30 minutes/one session (n=207) . The other was the age-matched “non-exercise group” who had no exercise habit (n=567) . Two-way ANOVA was employed for com paring the two subject groups and examining the effects of exercise on aging. Regarding sleep habits, as bed time significantly advanced with advancing age, sleep habits (bed time, waking time and sleep duration) were significantly more regular in the exercise group than in the non-exercise group. Concerning independent sleep health risk factors consisting of sleep initiation, sleep maintenance, sleep apnea, parasomnia, and waking-up, the factor score for sleep maintenance significantly deteriorated with advancing age; and was significantly better in the exercise group than in the non-exercise group. These results suggest that an exercise habit may improve sleep health in middle-aged and older Japanese women among which a higher prevalence of sleep problems has been reported.