Abstract: Picophytoplankton is responsible for much of the carbon fixation process and plays an important role in the active microbial food webs in the Arctic Ocean. Climate change is evident in the Arctic Ocean in recent years, picophytoplankton, as the most vulnerable part of high-latitude pelagic ecosystems, is receiving more attention. This summary mainly reviews the researches on picophytoplankton characteristics, including their abundance, biomass, spatial distribution, seasonal variation, community structure and the factors influencing their growth. In addition, the impact of climate change on picophytoplankton community and the prospect of this study field are also generalized.

Key words: Arctic Ocean, picophytoplankton, climate change, review