The continental shelf mechanism stipulated in the United Nations Convention on the Law of the Sea（UNCLOS）is the basic international legal framework for the delimitation of the extend continental shelf in the Arctic Ocean. To determine the outer limit of the continental shelf beyond 200 nautical miles，an application needs to be submitted to the Commission on the Limits of the Continental Shelf（CLCS）. The committee assumes two functions，respectively，for review and suggestion，and to provide advisory opinions. Other countries have the right to submit comments on the submission of the outer continental shelf submitted by coastal countries，and the CLCS shall discuss these comments. Russia，Canada，Norway and Denmark have submitted applications for the delimitation of the extended continental shelf in the Arctic region to the CLCS，and Norway’s application has been approved. At present，many countries have submitted comments on the submission of the extended continental shelf of the Arctic Ocean，but they are mainly concentrated in the coastal countries of the Arctic Ocean，especially the countries that have maritime disputes with the applicant country. Spain has submitted a commentary on the submission of Norway’s extended continental shelf，and its concern is limited to the reservation of the right to the continental shelf of Spitsbergen as a signatory to the Spitsbergen Treaty.