Using China's export trade panel data with 60 trading partners along "The Belt and Road", from the interactive perspective of culture and trade, this paper quantifies cultural communication effects by constructing a comprehensive evaluation index system including five first-level indicators and 13 second-level indicators, and using spatial Dubin model to study the influence of spatio-temporal evolution of Chinese culture promotion by the Confucius Institute on export. Our empirical evidence shows that:Firstly, while the scale of Chinese communication promoting by Confucius Institutes in countries along "The Belt and Road" has risen steadily, but the quality of communication is low, the sustainable development is slow and the comprehensive influence is uneven. The overall potential and quality of promoting communication and exchange between cultures and nations needs to be further developed. Secondly, cross-cultural communication arouse by Confucius Institutes has a positive role in increasing China's exports to the countries along "The Belt and Road". There is not only a significant interaction effect on the countries (regions) in which they are located, but also positive spillover effects on neighboring countries.