The Purpose of this paper is to compute the effects of changes in the composition of age, sex, and labor force participation rate, and education of population and labor force on the overall unemployment rate in Taiwan. The results show that the changes the composition of age-sex and labor force participation rate have had a increasingly significant downward pressure on the overall unemployment rate. However, the compositional changes in the education-sex have exerted considerable upward pressure on the overall unemployment rate increasingly, the policy-makers should pay attention to this phenomenon. It not only wastes the educational resources, but also will exercise unfavorable influence on Taiwan’s economic development in the future.