This paper attempts to summarize the transmission mechanism of China's infrastructure assistanceto Africa affecting China's direct investment in Africa. This transmission mechanism was empirically testedby constructing 16 infrastructure variables including 16 indicators from the two dimensions of infrastructurequality and quantity, and using transnational panel data from 39 African countries. The study found that, aftercontrolling market, resources, openness, population and other factors, China's infrastructure assistance toAfrica has a significant positive effect on China's direct investment in Africa. The demand of recipient countriesfor infrastructure is the main consideration of China's infrastructure assistance to Africa. However, China'sinfrastructure assistance cannot significantly improve the overall infrastructure level of recipient countries.