This study compared hydrography, microplankton, and mesozooplankton of the summer surface waters of three adjacent fjords in northwestern Greenland: Bowdoin Fjord, Inglefield Bredning, and Robertson Fjord. Bowdoin Fjord was warm and fresh, with high turbidity and chlorophyll, dominated by naked ciliates in microplankton and cyprid larvae in mesozooplankton. Inglefield Bredning was warm with low chlorophyll levels dominated by the small-sized copepod Acartia spp. and hydrozoan Aglantha digitale. Robertson Fjord was cold, saline, with low turbidity and dominated by dinoflagellates in the microplankton and nauplii of the large copepod Calanus hyperboreus. The eutrophic conditions of Bowdoin Fjord may accelerate the reproduction of benthic barnacles. The warm conditions and abundant food (small copepods) may allow the dominance of A. digitale in Inglefield Bredning. The oligotrophic oceanic conditions of the Robertson Fjord may allow the dominance of C. hyperboreus nauplii there. Under ongoing warming conditions in northwestern Greenland, the characteristics of Bowdoin Fjord and Inglefield Bredning may extend, while those of Robertson Fjord may diminish in the future.