We sought to examine the relationship between BMI, sweat rate (SR) and sweat volume (SV) in pre-, peri- and postmenopausal women during a moderate exercise. Based on their ages and menstrual cycle history, thirty healthy women were divided into three groups: pre- (22.5 ± 0.8 yrs, n = 10), peri- (46.5 ± 1.1 yrs, n = 10) and post- (52.2 ± 0.9 yrs, n = 10). Participants underwent a 15- minute walk on a treadmill at a constant speed of 4.2 km/h at 27°C. Sweat was collected and measured with a suction apparatus around a confined area of 120 cm² outlined on the skin of the face and neck of the participants during the exercise. SR and BMI were determined using the formulae: and   , respectively. The older women had a significantly higher BMI: pre-, peri- and post- (23.7 ± 1.3 kg/m² vs 28.0 ± 1.2 kg/m² vs 28.4 ± 0.7) (p < 0.05). Although there was no significant difference in SV (1.3 ± 0.4 ml vs 1.7 ± 0.2 ml vs 0.9 ± 0.1 ml) between the groups, the peri-women showed a significantly higher SR (0.07 ± 0.02 ml/min vs 0.12 ± 0.01 ml/min vs 0.06 ± 0.01 ml/min) (p < 0.05). A significant and positive correlation existed between BMI and SR (p < 0.05); SV (p < 0.01). Our findings support the conclusions that increased menopausal sweating is associated with weight gain/increased BMI especially during the perimenopausal transition period.