Abstract: Based on the panel data of high-tech manufacturing industry in 30 provinces of China from 2011 to 2019, this study uses the Output-oriented Directional distance function and the β convergence panel model of bi-directional fixed effect to measure the environmental efficiency of 30 provinces under the framework of Porter Hypothesis, and studies the convergence of the environmental efficiency of high-tech manufacturing industry in the Yangtze River Economic Belt. Some results show that: the intensity of environmental regulation in the Yangtze River Economic Belt has an “inverted U-shaped” trend, and the environmental efficiency in the upper, middle and lower reaches of the Yangtze River Economic Belt is increasing step by step. Environmental efficiency has a significant ?? convergence, and environmental regulation can drive the growth and convergence of environmental efficiency after short-term accumulation. There exists a virtuous cycle of “environmental regulation—increased investment in innovation—reduced economic benefit—emerging innovation benefit—improved environmental efficiency” in the high-tech manufacturing industry of the Yangtze River Economic Belt. In order to further improve the environmental efficiency of high-tech manufacturing industries in the Yangtze River Economic Belt, it is necessary to design reasonable environmental regulation intensity and appropriate environmental regulation policies according to local conditions, gradually improve the intensity of environmental regulation, and strengthen the “innovation compensation effect” of high-tech manufacturing enterprises.