<p>Environmental protection strategic alliances serve as a critical mechanism for enterprises to facilitate green transformation in response to stringent environmental regulations. Drawing on data from A-share listed firms in China spanning 2007–2022, this study explores how strategic alliances focused on environmental protection influence enterprises’ green innovation activities. The results reveal that strategic collaborations centred on environmental protection significantly enhance firms’ green innovation performance. The mechanism analysis demonstrates that these alliances contribute to improving firms’ green innovation performance through two main pathways: fostering higher levels of investment in environmental initiatives and promoting the transfer of environmental knowledge across organisations. The beneficial effect of environmental protection strategic alliances on firms’ green innovation becomes more significant under certain conditions, specifically when local authorities emphasise environmental governance, when the alliance is equity-based, when companies are backed by green-focused institutional investors, and when partner firms demonstrate a robust cooperative ethos. The findings of this study provide enterprises with strategic guidance for strengthening green innovation efforts during the transition toward sustainable development. Additionally, they provide valuable policy insights for regulatory authorities to guide enterprises to achieve carbon neutrality and peaking.</p>