This study uses listing firms of printed circuit board industry in Taiwan as empirical objects. The objective of this study is using S-C-P model to explore the influence of market structure, firm's conduct on operating performance. This work picks 43 firms in printed circuit board industry as empirical sample. The sampling period is from 1999-2007. The empirical results shows that firm size, investment intensity, R&D intensity and vertical integration (upward) have significantly influence on ROE; total asset, investment intensity and R&D intensity have significantly influence on income growth.