;According to the announcement in 2015 by IMD World Competitiveness Centre, the average working hours in Taiwan is more than the other 61 countries. Ministry of Labor also considers that there is too long in working hours and too much death in overworking in Taiwan. Therefore, they passed the law of working 40 hours per week. This law is valid or not depends on the willingness of overworking workers. However, the investigation time of research is before amendment of Labor Standards Law, overtime presents working above 42 hours per week. In addition, the research analyzes characteristics of overtime employees. This research uses Manpower Utilization Survey investigated by Directive General of Budget, Accounting and Statistics, Executive Yuan, R.O.C. The results of the regression analysis found that gender has an impact on working hours. Results depend on different situations, such as ages, education and numbers of children, not all of them have significant influence in choosing length of working hours. Finally, based on the results of this research, companies are recommended to take characteristics of overtime worker into consideration, and design proper human resources practice.