Abstract: The Arctic has been undergoing drastic environmental changes with the global warming, such as melting of sea ice, desalination of sea water, rising sea level, changing ocean currents and increasing ultraviolet radiation. The Arctic is one of the most sensitive regions response to global climate change. The special geographic location and the polar amplification effect make the Arctic Ocean ecosystem extremely vulnerable. As the primary producer, ice algae are the important components of the Arctic Ocean ecosystem and regarded as a good environmental indicator, which play important roles in the process of biogeochemical cycle and energy flow. Ice algae are sensitive to environmental changes, and it is greatly significant to study their responses to the global warming. The roles of ice algae are discussed in this paper from the aspects of their contributions to the Arctic Ocean ecosystem, including biomass, productivity, sedimentary organic carbon burial, and fishery resources. The responses of ice algae to the global warming are summarized according to the changes of their biomass, productivity, community structure, spatial and temporal distribution, and growth and export time. This paper provides relevant basis for the protection of Arctic Ocean ecosystem and the formulation of coping strategies for the global warming crisis.