農業是人類最重要的經濟活動之一，但從事農業需要投入許多並消耗大量的資源，其中尤以水資源的消耗最為驚人，考量到氣候變遷及社會發展對水資源供需的影響，管制單位如何誘使用水單位投入節水行為是當前的重要議題。本研究著眼於農業水資源管理，考量到水資源管理者與水資源使用者之間之資訊不對稱，本研究透過賽局理論模型建模，以委託代理之管制賽局機制設計觀點為基礎，將參與者分為用水單位（農民）及管制單位（政府），考量管制單位如何提供相應的誘因令用水單位盡力節水，並在最大化社會效益的目標下建立賽局與求解均衡，並且透過比較靜態分析及數值分析探討外生變數對於均衡解的影響並推導相關的管理意涵。本研究共建構兩個賽局模型，在基礎模型中只考量到管理者的補貼及用水者節水的數量，但在擴展模型中則加入了用水者努力程度的考量，研究中並探討在加入努力因素後會對整體系統產生的影響，努力因素將使系統更符合現實情況。本研究所推導的均衡解可以提供管制單位做為決策參考，明白如何在各種情境下提供適當的補貼並減少不必要的成本，亦可以提昇水資源分配的效率與社會的總體效益。

Agriculture, one of the most important economic activities of mankind, usually consumes a lot of water resources. In the era where climate changes and social development have led to serious impacts on the supply and demand of water resources, how the regulator design incentive schemes to induce irrigation water users to enhance water conservation behavior is an important issue. This study uses the concept of principal-agent theory to formulate and solve a game theoretic mechanism design model. In particular, participants of the game are divided into the irrigation water user (farmers) and the regulator (government), and the game is formulated in a way that the regulator provides incentives to make the irrigation water uses try their best to conserve water. We derive the equilibrium of the game under the goal of maximizing overall social benefits. Some comparative static analyses and numerical analyses have also been conducted to investigate the impact of exogenous variables on the equilibrium. The equilibrium derived by this study can be used by regulatory agencies to design appropriate subsidy polices to improve the efficiency of water resource allocation and to increase the overall benefits of society.

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