Abstract: Based on the data of listed companies in the upper reaches of the Yangtze River from 2015 to 2020， this paper empirically investigates the impact of the environmental protection tax policy implemented in 2018 on the total factor productivity of enterprises in the upper reaches of the Yangtze River by using the differenceindifferences （DID）. The conclusions show that the policy of environmental protection tax can significantly improve the total factor productivity of heavy polluting enterprises in the upper reaches of the Yangtze River， and the results still hold after a series of robustness tests. In addition， it takes time for the policy to have an impact on the total factor productivity， indicating that the policy has a relatively longterm effect. Compared with enterprises with higher TFP， the policy has a stronger promoting effect on the enterprises with intermediate TFP in the upper reaches of the Yangtze River.

Key words: policy of environmental protection tax; total factor productivity; differenceindifferences; upper reaches of the Yangtze River

摘要： 基于2015—2020年长江上游地区上市公司数据，采用双重差分法（DID），实证考察2018年实施的环境保护税政策对长江上游地区企业全要素生产率的影响。环境保护税会显著提高长江上游地区重污染企业的全要素生产率，该结果在一系列稳健性测试后依旧成立；环境保护税对企业全要素生产率产生影响需要一定的时间，说明环境保护税有一个相对长期的作用；相对于全要素生产率较高的企业，环境保护税对长江上游地区企业全要素生产率处于中间水平的企业具有更强的促进作用。

关键词: 环境保护税；企业全要素生产率；双重差分法；长江上游地区