企業價值評估是企業管理和企業投資的熱門問題，半導體產業又是高科技發展的關鍵。所以本文就台灣半導體產業的兩個晶圓代工企業之價值評估問題進行對比討論，分別用實質選擇權與自由現金流折現模型來對台積電和聯電進行價值評估。分析中發現實質選擇權方法在評價中比較能充分考量到企業投資決策的彈性，卻對於企業在行業中的領先地位比較難把握；而自由現金流折現模型對於財務報表的數據十分敏感，關於增長率的估計比較難把握，從而使企業價值評估的波動性較大，所以可以綜合兩個方法來進行評價，則可以減少估計誤差。本文的後半部分主要是基於半導體的產業狀況，對台積電與聯電兩家晶圓代工企業的經營策略進行分析，得出科技企業的經營收益與對技術研發的投入呈正相關，也與管理層的理念與穩定性以及上下游產業鏈穩定性密切相關。 / Business Valuation is an important issue for business management or business investment. The semiconductor industry is also an important part for high-tech development. Therefore, this paper focuses on the valuation of two foundry companies in semiconductor industry in Taiwan. Respectively, this paper uses the real option and the discounted cash flow models to assess the values of TSMC and UMC. The analyses find that the real option approach can consider the flexibility of enterprise investment strategy better than the discounted cash flow approach, while it is difficult to grasp the leadership of the company in the industry. The data from the financial statements is too sensitive for the discounted cash flow approach, and the uncertainty about the growth of a company contributes the volatility of the business valuation; therefore, by considering both approaches can reduce the valuation errors. The other part of this paper is based on the semiconductor industry analysis. With the comparison of the corporate business strategies of TSMC and UMC, we find that the operating income of scientific and technological enterprises is positively correlated with business investment in R&D, meanwhile it is closely related to the concept and stability of the manager, as well as the stability of the upstream and downstream supply chain.