Summary Objective This study aimed to investigate the effects of 6-month regular exercise and nutritional guidance for body composition, blood pressure, muscle strength and health-related quality of life (HRQOL) in community-dwelling Japanese women aged 40–74 years. Methods Participants were divided into an intervention group (n=48) comprising women registered for health guidance and a control group without intervention (n=66). The intervention group received 6-month exercise and nutritional guidance to modify lifestyle. Before and after the intervention period, body mass index (BMI), waist circumference, body fat percentage, blood pressure, muscle strength and HRQOL using the 36-item Short-Form Health Survey version 2 (SF-36) questionnaire were measured. Results At baseline, no significant differences were found between intervention and control groups. Waist circumference decreased significantly in the intervention group (from 82.4 to 79.9cm) compared to the control group (from 80.5 to 79.7cm). BMI and body fat percentage also decreased significantly more in the intervention group than in the control group. General health perception, vitality and social functioning in the SF-36 showed significantly greater improvements in the intervention group than in the control group. Conclusions Six-month regular exercise and nutritional guidance had beneficial effects on body composition and health-related quality of life especially for mental components of SF-36. Based on these findings, our intervention was expected to provide benefits to mental components of HRQOL and facilitate sustained participation and motivation in modify lifestyles. As a result, beneficial effects on body composition might also be sustained.