During summer and winter 2014, forty sediment samples were taken from Bahrekan Bay region using VanVeen grab (0.025 m2 area). According to the results, 59 species and 52 Genus were identified. There were a positive correlation between %TOM, %Silt and Clay fractions and macrofaunal assemblages. The dominant species in all studied stations were Cerithium sp., Cerithidea cingulata, Pseudonoba sp.2, Tornatina persiana and Paraprionospio pinnata. Grain size analysis showed that the substrate of study area was muddy. The highest %TOM ranged from 6±0.15 to 20.76±0.33 in winter. The results showed that the positive correlation between %TOM and %Silt and Clay were r=0.79 in the summer and r=0.48 in the winter. The highest and lowest number of individuals of macrofauna were counted in summer (2038 ind. / 0.025 m2) and winter (1722 ind. / 0.025 m2) respectively. During this study, Bivalves were the dominant group (%39.14) followed by Gastropoda (%38.47), Polychaeta (%19.23), Crustacea (%2.92), Scaphopoda (%0.17), Echinodermata (%0.07) and Soft Corals (%0.04). The comparison of H&prime values with Welch model showed that study area is in the moderate level of this model with low species diversity.