冰盖（ice sheet）是指连续的冰川冰覆盖了50,000 km（19,000 sq mi）以上陆地，因此也称作大陆冰川（continental glacier）。目前仅有的冰原是南极洲与格陵兰。在末次冰期的冰盛期，劳伦泰冰原覆盖了北美洲广大陆地， 威赫塞尔冰原覆盖了北欧，巴塔哥尼亚冰原覆盖了南美洲的南部。

冰原大于冰架或高山冰川。面积小于50,000 km称作冰帽。冰帽的四周通常孕育了多条冰川。

虽然冰盖的表面是寒冷的，但冰盖的底部由于地热作用通常是比较温暖。因此，在底部出现冰融，冰融水起到润滑作用使得冰盖流动更为迅速。这种过程产生了冰盖的快速流动部分 —冰流（ice stream）.

An ice sheet is a mass of glacier ice that covers surrounding terrain and is greater than 50,000 km (19,000 sq mi), thus also known as continental glacier. The only current ice sheets are in Antarctica and Greenland; during the last glacial period at Last Glacial Maximum (LGM) the Laurentide ice sheet covered much of North America, the Weichselian ice sheet covered northern Europe and the Patagonian Ice Sheet covered southern South America.