Abstract:     The deep integration of digital economy and real economy is not only reflected in the deepening of enterprise digital transformation, but also in its structural optimization. How to promote high-quality economic development with high-quality transformation has been given new significance in digital economy. This paper used the data of Shanghai and Shenzhen A-share listed companies from 2007 to 2021 to explore the impact of enterprise digital transformation structure on innovation strategy. We found that: (1) the enterprise digital structural optimization significantly promotes the innovation strategy to substantive innovation, and independent innovation ability enhancement, human capital re-upgrading, operating cost reduction are important channels; (2) when the degree of innovation competition in the industry, the quality of labor supply in the region and the support from innovation incentive policies is lower, the digital structural optimization has a more obvious promoting effect; and (3) the impact of subdivided digital technology structures on innovation strategy has both commonalities and characteristics, and the digital structural optimization promotes the concentration of innovation fields and the strengthening of innovation spillovers. From the perspective of structure, this paper has enriched the research on enterprise digital transformation, and it will provide solutions for how to alleviate the problem of "valuing quantity over quality" in innovation, thus having implications for enterprises to choose digital transformation paths and governments to design digital economic policies.

Key words:  digital transformation, innovation strategy, substantive innovation, strategic innovation