Using the large-scale micro data from China industrial enterprise database and China Customs Trade database, we can empirically analyze the impact of the import of intermediate goods on R & D investment of industrial enterprises in Beijing based on the enterprise level. Theoretically, on the one hand, the import of intermediate goods will promote the ability and level of enterprises to carry out innovation activities through "learning from import" and market size effect, and stimulate the innovation motivation of enterprises by "escaping" from competition; on the other hand, it may also solidify the enterprises at the low end of the value chain and form dependence on imports, thus making enterprises completely lose the ability of independent innovation. The empirical results show that: the import of intermediate goods significantly promotes the R & D investment of industrial enterprises in Beijing, especially for enterprises engaged in export trade, enterprises engaged in general trade, private enterprises, and enterprises importing capital goods and intermediate goods at the same time, but it has inhibitory effect on R & D investment of non-export enterprises and state-owned enterprises. Therefore, Beijing municipal government should attach great importance to the important role of the import of intermediate goods in promoting innovation activities of enterprises, help enterprises solve the unfavorable factors restricting import, actively encourage specific enterprises with R & D capabilities to upgrade the scale of the import of intermediate goods and optimize the import structure, so as to further enhance the independent innovation ability of enterprises.
