Platform-based companies are rapidly emerging and occupy major positions in the global market. In addition, the business model that relies on digital technology makes platform-based companies sustainable. This paper empirically examines the impact of internationalization breadth on corporate performance and explores the moderating role of the platform enterprise network effect and innovation investment. Annual panel data from listed Chinese platform-based companies between 2012 to 2020 were used to also verify the scale of overseas companies’ association and social networks and the moderating effect of centrality and innovation research and development (R&D) investment on these two factors. The results indicate that the irregular internationalization rhythm of platform-based companies was negatively correlated with corporate performance, and the association network and the social network centrality of overseas companies had a positive moderating effect. Innovative R&D investment could help platform-based companies expand overseas to improve their corporate performance, and its moderating effect was more significant for platform companies in the early stages of internationalization. In terms of the internationalization pace, overseas network construction, and innovative R&D investment strategies, this paper provides valuable suggestions for platform-based companies to expand internationally and improve their corporate performance.