To clarify the influences of ethnic and regional characteristics, and differences in perception on the cedrol effect on autonomic nerve activity, we compared women in their 20s-40s in Norway, Thailand, and Japan. A questionnaire survey of sense of stress and sleep conditions was performed at the same time. The degree of perceived stress, using a 30-item checklist, was highest in Japanese women. The mean stress score exceeded 5.0 in Japanese women, significantly higher than in Thai women (p<0.05) and Norwegian women (p<0.01). Sleeping time was shortest in Japanese women in all generations among the three countries. As the index of autonomic nervous activity, the miosis rate (ratio of pupil-diameter variation after light stimulus to initial pupil diameter) in pupillary light reflex was measured before and after cedrol inhalation. The miosis rate significantly increased after cedrol exposure compared to that before exposure in all three countries, suggesting that the parasympathetic nervous system became dominant. These findings suggested that cedrol produces a sedative effect in people of the three countries despite differences in the ethnic and living environments.