The R.O.C's civil service system has been reformed three times after the government moved into Taiwan in 1949. During the latest reformation, Rank Assortment Personnel System with Ranks and Personnel System with position Classification were united into the present personnel management system, enforced on Jan 16, 1987. It is based on four Civil Service Acts of examination, employment, pay and performance evaluation, each amended several times to meet the requirement of national development, governments, and social and political environment change. As the system has been enforced for 20 years, this article would like to review the system's structure and change, and to provide some opinions for the authorities??reference to further the system.