Following the new trend of the global economy, in the era of industry 4.0, ecommerce activities are becoming more and more popular. The scope of e-commerce activities has erased the concept of national borders and territories. This opens up a variety of transaction methods in the field of e-commerce following the trend of globalization. Along with positive contributions to growth and restructuring of the world economy, the emergence and rapid development of cross-border e-commerce activities also poses challenges to state management in each country, including tax administration issues. In Vietnam, cross-border e-commerce activities also follow the general trend of strong development. Accordingly, the tax state management agency must both ensure conditions for entities conducting cross-border e-commerce activities to participate in the economy in a healthy way, bring sustainable economic benefits, and strictly comply with the tax law framework in the host country. In the article, the authors make assessments on tax administration for cross-border e-commerce activities; some current situations and challenges in this field. The authors also propose a number of solutions to improve efficiency in cross-border e-commerce tax management. Keywords: e-commerce activities, cross-border, tax management.