The economic complexity measured by exports reflects the technical content of an economy’s exports, which can explain and predict economic growth. In the Silk Road Economic Belt, most countries’ economic complexity lies in the middle or lower position of the global production network division of labor. This paper uses the empirical methods like two-step system GMM to analyze the influential factors of the regional economic complexity. The result shows us that lagged economic complexity, innovation, infrastructure and human capital have significantly positive impact on economic complexity, and institution and the logarithm of average GDP have significantly negative impact, while physical capital and intensity of intra-product specialization don’t have significant impact. China holds significant advantage indexes in economic complexity, R&D investment and physical capital, and has certain advantages in institutions and infrastructure, but China’s relative weakness in human capital can not be ignored.