The purpose of this study is to evaluate the economics impacts of the alternative tariff reductions on social welfare, producers' surplus, agricultural production value, labor, and planting acreage by using Taiwan Agricultural Sector Model. Such empirical estimation results may have important implication for policy decision. Our findings show that the social welfare increases as the tariff reduction increases while consumers and producers surplus depend on demand and supply elasticity. Higher demand and supply elasticities results a significant change both in consumers and producers surplus. We also found that the tariff reduction level significantly affects agricultural production value. However, such impact for each individual product is different regard of same tariff reduction level. The impacts of tariff reduction on land and labor usage is also significant which implies possible policies adjustment with respect to factor markets are needed.