国际经济活动的主要比较方法是市场汇率和购买力平价。由于市场汇率有可能大幅度偏离购买力平价,这两种比较方法有可能存在很大的差异。如果对中国与发达国家的国内生产总值进行比较,用市场汇率的方法严重地低估了中国的产值,但用购买力平价的方法又高估了中国的产值。本文分析了这两种比较方法差异的原因,并据此揭示了国内生产总值比较中存在的问题以及表面公平而实际不公平的国际贸易格局。 The main comparisons of international economic activity are market exchange rates and purchasing power parities. As the market exchange rate is likely to deviate significantly from the purchasing power parity, the two comparison methods may be very different. If we compare China’s GDP with developed countries and seriously underestimate the value of China’s output by using the market exchange rate, China’s output will be overestimated by the purchasing power parity method. This paper analyzes the reasons for the differences between the two comparative methods and reveals the problems in the comparison of the GDP as well as the unfair international trade patterns, which are fair in appearance.