Phytoplankton taxa and abundance were determined and nutrients and chlorophyll a were measured in the Babadillimam Bight located in the northeastern Mediterranean coast of Turkey. Sampling was performed four times between the period of 1999 and 2000. The concentration of, PO4-P, NO3+NO2-N and [Si(OH)(4)]-Si in Surface water varied in the range of <0.01-0.22 muM, 0.37-1.23 muM and 0.52-2.02 muM, respectively. Surface water phytoplankton abundance reached the highest level (572.4 x 102 Cells 1,I) in March mainly due to the increase of a diatom, Skeletonema costatum. It reached the lowest level in August (3.36 x 10(2) Cells l(-1)). Chlorophyll a concentrations ranged from 0.1 mug l(-1) to 0.87 mug l(-1) in surface water. Nutrient concentrations and phytoplankton biomass of the research area were found poorer than those or the many other coastal areas in the region and the other world oceans. Although the study was performed in a coastal area, the results reflect the oligotrophic nature of the eastern Mediterranean.