本研究主要係延續過去所做的有關臺灣產業結構與集中度方面的研究，利用主計 處臺閩地區工商普查的原始資料分析產業集中度在1976年到1991年間的變動情形，及探討 1981-1986、1986-1991、1981-1991年影響集中度的因素，並分別比較資本財、消費財、中 間財產業，高、低集中度產業以及內外銷產業集中度決定因素的差異。本文的實證結果除對 臺灣產業結構的變化提出重要的數據說明之外，並驗證多項產經的理論。

　　　　　The purpose of this paper is to investigate the level of Taiwan industry concentration during 1976-1991, and how it changed. The determinants of the con- centration and its changes are probed to analyze the characteristics of industry structures. The data used in the paper were quoted from the report on industrial and commercial census, Taiwan-Fukien area, the Republic of China. The main empirical results are that the trend in aggregate concentration was declining between 1976-1991, but manufacturing concentration appears down during 1976-1986 and up in 1991. We found that industry growth and product differentiation are the main reasons for the increase in 1991 concentration. Moreover, we found that the determinants of concentration and its changes include barriers to entry, MES, industry growth, size of industry, production differentiation, level of beginning concentration, net entry rate, etc. Our results confirm several industrial economic theories.