「半總統制」是Duverger於1980年在《歐洲政治研究》期刊中，首次以英文發表，自此引起學術界的熱烈討論，新興民主國家的憲政體制也紛紛選擇「半總統制」，我國也在第四次修憲後成為「半總統制」之一員。對「半總統制」理論的探討與實際憲政運作的比較分析，乃有其必要性與重要性。
本論文主要在比較法、我兩國憲法規範與憲政運作之差異，探討何以法國第五共和憲法與我國在憲政制度設計上均為「半總統制」國家，但是，憲政運作的結果卻呈現截然不同的面貌？本研究一方面比較兩國制度上之差異，一方面分析其他影響因素，將前述以及其他造成運作差異之重要因素進一步作學理上之整體分析，並進一步建構相關因果模型，以供進一步經驗研究之參考。且歸納得岀「半總統制」憲法規範的界限，並解釋憲法組織篇所建構憲政運作之基本規則，憲政運作應該在「界限」與「基本規則」之間所形成的軌道內運行，如此憲法方具有規範意義。違憲審查之效果，若係違反「界限」層次，則警告其有違憲之可能，若係違法「基本規則」，則可宣告違憲而無效。此模式之建立在實務上有助於建立司法對憲政運作審查之可操作化基準，在理論上提供政治學與法學的對話平台，以利形成我國憲政體制類型之通說。

The idea of ‘semi-presidential system’ was proposed by Duverger (1980), and it aroused substantial following studies. Newly rising democratic countries have also adopted semi-presidential system. After 1990, Taiwan also adopted a semi-presidential systems right after the constitution revised. As the member of the system, the understanding and improvement of theoretical and practical for the system is necessary and timing.
This study will plan to compare the constitutional frameworks and operational types of semi-presidential countries between France and Taiwan. We try to find the variables that influence the constitutional operation. We expect this study can provide a causal model for the further empirical research. After compare the constitutional statues and its operations difference between France and Taiwan, we have the constitutional statues boundary of semi-presidential system. We also have the constitutional operations basic rule by constitutional interpretation. To be a normative constitution, that is, its norms govern the political process or the power process adjusts itself to the norms, constitutional operations should be operate between the “boundary” and the “basic rule”. We expect this study can provide a dialogue platform between political science and law and construct an operative standard for judicial review.