Abstract This text, referred to the manpower survey data in 1991 & 2003 obtained from the Accounting & Statistics Department, is aimed at making a study of the trend on the switch of occupation before and after the rise of the Knowledge-based Economy Age. The employees, having experiences of switch, are chosen from the data of the Accounting & Statistic Department for ongoing intersecting analysis of before and after their switch. This research has found that the turnover of occupation/profession, within the time before development of the knowledge-based economy Age of 1991, has been prone to the mass-labor industries, such as traditional manufacture, construction and etc. Amid those labor mobility, industries which having failing net turnover rate of 2003, include the ones of ¡§Professional, Scientific and Technical services¡¨ and ¡§Cultural, Sporting and Recreational Services.¡¨ It shows that Taiwan is appropriate to a new market with reconstructed labor and reacts clearly in that the supply of employees were not quick enough to catch reshuffled employment market. Possessing the first and second place among those industries are that ¡§Technicians and related¡¨ and ¡§Machine Operators & Fabricator¡¨ that are failing on the net turnover rate, are well in parallel with two industries of ¡§Construction¡¨ & ¡§Real Estate and Rental and Leasing ¡§ that are keeping minus on the net turnover rate. Furthermore, it shows that the traditional mass-labor industries have entailed labor to flow outward massively. The labor released from swift labor restructure is the major reason what causing the massive number of unemployment in the labor market. In the past twelve years, the structure of occupation of Taiwan¡¦s employees is changed from mass-labor to mass-technique, and developed toward the service-industry steadily. The dominant phenomenon existing together in current labor market are that both unemployment and insufficiency of labor.