<p>The Polar Silk Road (PSR), a key initiative of the China–Russia cooperation in Arctic affairs, holds significant potential for the sustainable development of the Northern Sea Route (NSR). However, scholarly attention on the role of marine environmental protection in this ambitious project remains insufficient. This study examines the interplay between the PSR and marine environmental protection and highlights the challenges that hinder its successful implementation. These challenges include underdeveloped Arctic marine environmental regulations, sanctions imposed by Europe and the United States on the NSR, and the inherent fragility of the Arctic ecosystem. The study proposes the establishment of a Green PSR framework and outlines key recommendations for effective marine environmental protection. It includes the development of robust legal frameworks, the promotion of green shipping practices, and the strengthening of cooperative mechanisms among nations involved in the PSR. By fostering transparency and collaboration, China and Russia can address concerns from other countries, particularly those along the NSR, and encourage full participation in the initiative. This collaborative approach will contribute to the establishment of comprehensive regulations for marine environmental protection in the Arctic, thus reinforcing the role of the PSR in sustainable development and safeguarding the delicate environment of the Arctic.</p>