In this study, the performance of ISO 9002 in public sector was evaluated by customers' satisfaction, especially in the Bureau of Labor Insurance. In this paper, the customers were divided into internal and external ones. The measurable indicators included both of their satisfaction. The data was collected by survey and analyzed by Chi-square, t-test. The results revealed the followings: The external customers' satisfaction declined after ISO 9002 was implemented. The internal customers thought ISO 9002 was helpless to promote the efficiency and service quality but improved the image of the administrative organization. In conclusion, ISO 9002 was ineffective to the service quality and customers' satisfaction of the Bureau of Labor Insurance.