中文摘要：

本文以我国原油特别收益金政策为例，分析了意外利润税在不同市场结构下对可耗竭资源开采的价格路径、最初价格和社会福利的影响。以Hotelling的社会福利最大化的可耗竭资源价格路径作为评价基准，分析说明通过合理设定基准价格和税率水平，能保证在不同市场结构中实现社会福利最大化，据此作为我国原油特别收益金政策效果的理论依据。

英文摘要：

This paper takes Special Oil Gain Levy as example and compares the price path and the initial price of extraction of exhaustible resources and social welfare under alternative market structures when the windfall profits tax was imposed. Hotelling＇s optimal extraction path can maximize social welfare, which serves as the evaluation benchmark of this paper. The analysis of the influence of the windfall profits tax shows that the optimal extraction path of exhaustible resources is associated with the base price and the tax rate. And in both markets, this exist the optimal taxation which can optimize the total social welfare. The conclusions of this paper provide the theoretical basis for Special Oil Gain Levy.