We examined the validity of ‘Transtheoretical Model of Behavior Change’ six stages in exercise domain. A paper-pencil survey was completed by 457 workers. Self-efficacy tended to increase from Precontemplation to Action, did not change from Action to Maintenance, and then increase from Maintenance to Termination. Pros tended to increase and cons decrease only from Precontemplation to Action. A follow-up survey was completed by 331 workers. More preparers (25.4%) moved to Action compared to precontemplator (3.8%) and contemplators (6.5%). Relapse rates were lower among those in Termination (17.0%) than those in Action (43.8%) and Maintenance (38.1%). These results partially supported the validity.