農業係屬攸關民生之重要產業，對任何國家而言，糧食安全問題自是不容忽視。本文嘗試建立一個聯結農產品市場、製造業產品市場、貨幣市場以及官方農產品存量調整式之動態理論模型，據以探討因干擾產生致使農產品存量體制由自由浮動崩潰為固定管制的過程中，經濟體系相關變數之動態走勢。經由本文分析發現，政府所設立的門檻水準之高低不僅左右農產品存量體制由自由浮動轉爲管制固定的時機，而且對政府為執行安全存量政策所需調整的農產品購買水準以及農產品價格波動幅度亦深有影響。

Agriculture is a key industry for human survival. For any country, food safety and security are important issues that can't be ignored. In this article, we propose a new dynamic model which includes the agricul­tural product market, manufactured product market, monetary market and adjustment formula of official stock for agricultural products. We also investigate the adjustment path of economic variables from flexible regime to regulated regime when the economy faces supply shock. The result shows that the threshold level set up by the government is a deter­minant factor in the timing of flexible regime collapse. It is also a deter­minant factor in the amount of food purchased by the government for food security and the degree of flexibility of agricultural prices.