The Oslo Declaration on High Seas Fishing in the Central Arctic Ocean (CAO) signed in July 2015 reflects the common interests of the Arctic coastal states (namely, the A5) to manage fisheries in the Central Arctic Ocean beyond national jurisdictions. As a multilateral document with a soft-law nature, the Oslo Declaration was followed by the ‘A5 plus 5 (the EU, Iceland, China, Japan, and South Korea)’ negotiations towards a legally binding agreement. However, questions remain unsolved. For example, to what extent can the Oslo Declaration or other following-up instruments be used for the CAO high seas fishery management? Moreover, under international fisheries law, are there any loopholes of the current fishery management under the ‘A5 plus 5’ negotiation framework? This paper provides an overall examination on the legal aspects of the Oslo Declaration, especially the arguments regarding the future of fisheries management in the High Seas portion of the Central Arctic Ocean, such as a Regional Fisheries Management Organization (RFMO) or Agreement (RFMA) as the interim measure, and the differences between the Declaration and international fisheries law.