Abstract:     Joining the digital ecosystem led by platform enterprises as complementary enterprises for innovation has gradually become the dominant way for small and medium-sized enterprises to innovate, but the cooperative and competitive relationship between the two will increase the uncertainty of complementary enterprise innovation. This article is based on the perspectives of knowledge governance and competition theory, and constructs a model to explore the impact of ecological governance and complementary market entry decisions of platform enterprises on the innovation of complementary enterprises. A multi-layer regression analysis method is used to analyze questionnaires from 297 complementary enterprises in the digital innovation platform ecosystem. Research has found that: (1) Although the mechanism is varied, the market-based, society-based and hierarchy-based governance of the platform ecology has a significant positive role in complementary enterprise innovation; (2) The complementary market entry behavior of platform enterprises can suppress complementary enterprise innovation; (3) Platform ecological governance can weaken the negative impact of complementary market entry behavior on complementary enterprise innovation. The balance between platform ecological governance and complementary market entry reflects the essence of the competitive and cooperative relationship between platform enterprises and complementary enterprises, which helps to promote the innovation of complementary enterprises. The research results will contribute to enriching the innovation theory of SMEs under the background of platform ecological governance and digitalization and deepening the research on the relationship between platform enterprises and SMEs. The study will also provide useful guidance for SMEs to realize innovation through digital transformation.

Key words: platform enterprise, platform ecosystem governance, complementary market entry, complementary enterprise innovation