本文探討有機農產品標章（organic agricultural product label）之雙重紅利效果；並且以實例說明有機農產品標章對社會福利的影響。本文模型的市場結構為兩家農產品供應商決定是否採取有機植栽技術以生產有機農產品。因為農產品施作時使用氮肥會產生溫室氣體氧化亞氮（nitrous oxide, N2O），所以政府部門促進N2O排放減量以極大化社會福利。研究結果發現：推行有機農產品標章可以減少N2O的排放量，提高消費者剩餘；亦即建立有機農產品標章制度有雙重紅利（double dividend）效果。由於行政院農委會所屬的農業改良場是我國主要的農業技術研發單位，透過技術移轉可以大幅降低民間廠商研發植栽技術的成本，又我國稻米供應的兩大龍頭公司，只有一家廠商擁有自己的有機農場並且進行有機植栽技術研發，故社會福利有再提昇的空間。

This study investigates the double dividend from an organic agricultural product label and looks at a real case to illustrate the influence an organic agricultural product label has on social welfare. Our model structure takes on two agricultural product suppliers that decide whether to adopt organic farming or not in order to obtain an organic agricultural product label. If the agricultural product supplier uses nitrogen fertilizer for farming, then it emits Nitrous Oxide (N2O), which is a greenhouse gas (GHG). At this time, the social planner decides to reduce the amount of N2O emissions in order to maximize social welfare. We conclude that the regulation of an organic agricultural product label can cut N2O emissions and promote consumer surplus. In other words, setting up an organic agricultural product label creates a double dividend effect. The Agricultural Research and Extension Station, Council of Agriculture, Executive Yuan is the main unit of research and development (R&D) in agricultural farming technology in Taiwan. By technology transfer and licensing, it can sufficiently help reduce a private firm's R&D cost in agricultural farming technology. Since there are two large-size rice suppliers in Taiwan, but only one supplier has its own organic paddy field and does organic farming technology R&D, social welfare in this area has room for improvement.