國內重大基礎建設BOT案常因較長興建期及較高興建成本之計畫財務特 性，使得BOT案先天上不易具備完全自償性（計畫自償率< 1)。因此政府必 須提供足夠財務誘因做爲實質的獎勵措施，才能促使民間投資者有參與國家基 礎建設之意願。一般最直接有效的政府獎勵措施，就是由政府直接出資補助部 分的興建成本。政府應出資補助多少才是最佳補助額度，國內一般是以計畫觀 點專案自償率，作爲政府補助金額之主要參考依據。本研究提出一套財務分析 模式及考慮計畫價値極大化之線性規劃模式，以決定政府、民間投資者、融資 者之三方最佳出資比，也就是分析專案計畫之最佳資本結構。本研究在分析三 方最佳出資比時，配合實務上兩階段商務談判之談判行爲，首先是第一階段政 府與民間投資者之間的談判，該次談判主要是授予投資者BOT案之特許權及 決定政府出資補助的額度，以臺灣高速鐵路案爲實證案例分析，模式計算結果 爲政府應出資補助比是40.53%，民間應自籌59.47%。第二階段是投資者取得 BOT案特許權後，投資者與銀行之間的融資談判，該次談判主要是確定投資 者的出資比與融資者同意之融資成數，模式計算結果爲投資者最佳出資比爲自 籌資金部分之27.22%，融資者之最佳融資成數爲自籌資金部分之72.78%。

Due to the lengthy project term and huge project cost, full selfliquidation is rarely possible for major infrastructure projects operated in the build-operate-transfer (BOT) model. The government thus needs to provide substantial financial incentive to attract investors, and direct government financing of the construction cost is the most effective incentive. In Taiwan, the optimal amount of government financing is usually determined according to the self-liquidation ratio (SLR) of projects. This study proposes two models to determine the optimal financial structure of the BOT projects; that is, the amount of investment of the government, the investors, and the banker. These models include a two-stage negotiation: government-investor and investor-banker negotiations. The former focuses on the franchise awarded to the investor and the amount of government financing. The latter emphasizes the credit the banker provides for the investor. Based on the case of the Taiwan High Speed Rail (THSR), the optimal financial structure between the government and investor is 40.53% and 59.47% respectively; and the optimal financial structure between the investor and banker is 27.22% and 72.78% respectively.