台中縣市已於2010年12月25日正式合併升格為直轄市，本研究首先將從制度量能的分析觀點，說明合併前、後台中市的制度量能狀態，其次則是以公共支出的分析觀點，運用Urban Taiwan的8項永續發展指標，以趨勢圖的方式呈現合併前台中市的永續發展指標的變動趨勢，並分析公共支出是否在提升永續性上發揮了作用。研究結果發現，第一，合併前的台中縣、市政府的制度量能是不足的，永續發展綱領性文件、永續發展委員會與永續發展指標系統僅有名目功能，而無實質功能；第二，合併後的台中市的制度量能建構則缺乏進展，特別是至今仍缺乏高位階的永續發展綱領性文件、永續發展委員會被弱化、以及缺乏可有效發揮政策導引功能的永續發展指標；第三，觀察合併前的台中縣、市的永續性，台中市有4項指標是邁向永續，台中縣則有6項指標是邁向永續；第四，合併前的台中縣、市，公共支出與永續發展指標的連結上都顯得薄弱。基於上述分析結果，本研究認為後台中市應加速完成正式的永續發展綱領性文件，調整永續發展委員會的主任委員位階與委員組成比例，並落實永續發展指標的建構工作，提升永續發展的制度量能層級，使得政策得以有效轉化，實質化的導引後台中市邁向永續發展治理之路。

Building of sustainable institution plays an important role in the practice of sustainable development. Based on the institution capacity model, this paper analyzes the theoretical content and examines the state of sustainable development and sustainability of public expenditure in Taichung city in Taiwan. In this paper, institution capacity was divided into three evaluation items, including guideline document of sustainable development, council for sustainable development and sustainable development indicators, to analyze the state of institution capacity in Taichung city, Taichung County and new Taichung city respectively. Eight sustainable development indicators of urban Taiwan system were used to analyze the sustainability in Taichung city and Taichung County. Our research finds four noticed institution problems. First, institution capacity is not sufficient. Second, sustainable development indicators are not effective for policy leading. Third, Taichung city and Taichung County did not perform well on the sustainability. Fourth, connection of public expenditures and sustainable development indicator is really weak. Lastly, this paper suggests the authority reviews and renews guideline document of sustainable development and council for sustainable development should be adjusted. More important is construction of sustainable development indicators for new Taichung city. Meanwhile, mechanisms formulated by institution capacity would promote sustainability more efficiently. The authority should keep on promoting the level of institution capacity to make policies toward sustainability.