利用国地税合并事件，采用双重差分方法分析国地税合并对企业异地投资的影响。研究发现，国地税合并能够减少企业异地子公司数目。机制检验表明，国地税合并通过区域税收征管、企业利润转移空间来抑制企业异地投资。进一步分析表明，国地税合并能够精准识别不同类型企业，增加避税类的异地投资企业实际税负，而对真实类异地投资企业的税负没有实际影响。异质性检验表明，其治理效应在异地子公司所在地区的政府干预强、法制环境差和民营企业样本中更显著。

This paper uses the difference-in-differences method to analyze the impact of the merger of national and local taxes on the non-local investment of enterprises. The study found that the consolidation of national and local taxes can reduce the number of non-local subsidiaries. The mechanism analysis shows that regional tax administration and space for profit transfer are the related mechanisms. Further analysis shows that the merger of national and local taxes can effectively differentiate different types of enterprises, which increases the actual tax burden of non-local investment enterprises in the tax avoidance category, but has no significant impact on the tax burden of real non-local investment enterprises. The impact of the merger of national and local taxes is obviously heterogeneous, and its governance effect is more significant in the strong government intervention, poor legal environment and private enterprises in the regions where the non-local subsidiaries are located.