北冰洋（英语：Arctic Ocean）又称北极海、北大洋，位于北极圈内，大致以北极点为中心。北冰洋是世界五大洋中最小最浅的。面积1405.6万平方公里，约占世界大洋面积的3.6%。平均深度1200-1300米，为世界大洋平均深度的三分之一。最深处为南森海盆，深度为5450米。

国际航道测量组织将北冰洋视为是洋，不过一些海洋学家称之为「北极陆间海」或是「北极海」，分类为陆间海或是大西洋的河口湾。

北冰洋有巴伦支海、波弗特海、楚克奇海、东西伯利亚海、格陵兰海、哈得逊湾、哈得逊海峡、喀拉海、拉普捷夫海、白海和巴芬湾等边缘海和陆间海。

The Arctic Ocean (also known as the Northern Ocean), located in the Northern Hemisphere and mostly in the Arctic north polar region, is the smallest and shallowest of the world's five major oceanic divisions. The International Hydrographic Organization (IHO) recognizes it as an ocean, although some oceanographers call it the Arctic Mediterranean Sea or simply the Arctic Sea, classifying it a mediterranean sea or an estuary of the Atlantic Ocean. Alternatively, the Arctic Ocean can be seen as the northernmost part of the all-encompassing World Ocean.