Taking 11 provinces and cities in the Yangtze River Economic Belt as the research object, based on the combined model of PCA-SE-DEA theory, this paper quantitatively tests the scientific and technological innovation efficiency, analyzes the factor system affecting its development process, focuses on the technological innovation efficiency of the Yangtze River Economic Belt, and conducts convergence testing and analyzes its influencing factors and causes. At the same time, based on the C-D production function, the paper analyzes the correlation between technological innovation and economic development factors in the Yangtze River Economic Belt. The research results show that:the efficiency of technological innovation in the Yangtze River Economic Belt has not reached the average level in China at present; the provinces and cities in the Yangtze River Economic Belt show regional differences in the efficiency of technological innovation, and this difference shows an upward trend. Among the influencing factors, the optimization and upgrading of regional industrial structure has the greatest impact on the technological innovation efficiency of the Yangtze River Economic Belt. Among them, investment in science and technology, output of science and technology and environment of science and technology are particularly important for the good development of regional economy. The supporting efficiency of science and technology innovation for economic development is generally effective, with obvious regional differences. Therefore, the Yangtze River Economic Belt needs to adjust and plan as a whole, build a coordination mechanism, realize a good operation system of overall innovation and entrepreneurship in the basin, and improve the efficiency of technological innovation in an all-round way.