Chapter 2 reviews existing literature on the impact of green trade barriers on the green transformation of enterprises. The literature is divided into two main strands. First, the environmental effects of international trade, examining the relationship between trade and environmental outcomes, including the effects of trade liberalization and barriers. Second, the paper explores green trade barriers specifically, detailing their types, measurement methods, and impact mechanisms. The review highlights that while much research has been conducted on trade’s environmental impacts at the macro level, there is a gap in micro-level studies, particularly in developing economies. It also notes the methodological challenges in measuring green trade barriers and advocates for more firm-level research to understand their effects. The chapter concludes by identifying the need for further investigation into how green trade barriers influence technological innovation and sustainable development, especially in developing countries like China.