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Macrobenthos always play a significant role in the food web of any coastal environment. It also uses as a good aquatic ecosystem health module indicators. The abundance and distributions of macrobenthos in Rezukhal, Cox's Bazar were conducted in relation to hydrological parameters. Samples were collected monthly during June-2015 to May-2016 from three separate stations use different scientific instruments at Rezukhal estuary. A total of 7662 individuals of macrobenthos were counted in total of III stations. Macrobenthos were comprised of six major groups namely Polychaeta (52.22-91.57%), crustacean (3.79-8.09%), Bivalvia (1.05-2.27%), Nemertia (0.79-1.60%), Sipuncula(0-8.55%) and Gastropoda (1.36-31.92%). Total number of macrobenthos was higher at station I (4197 individuals m-2) and lower at station II (1186 individuals m-2) among three stations. The study revealed that highest no. of Macrobenthos were found in Post monsoon period about 3146 individuals m-2 and lowest in Premonsoon period about 1995 individuals m.-2 The average soil and water P H were found in monsoon (5.87&7.45), Post monsoon (5.97&7.28), Premonsoon (6.03&7.33) respectively. The average salinity was found in monsoon (11.92ppt), Post monsoon (25.91ppt), Premonsoon (28.75ppt) respectively. The average spring tide and neap tide level were found in monsoon (15&3.04 ft), Post monsoon (12.67&1.36 ft), Premonsoon (11.28&1.16 ft) respectively. The average soil and water temperature were found in monsoon (28.67&27.67 o C), Post monsoon (29.41&28.5 o C), Premonsoon (29.42&29.83 o C) respectively. Soil moisture ranged was from 26.36-35.07%. The highest organic carbon and organic matter concentration was observed at station I (2.58%-4.3%) and lowest at station II (1.59%-2.96%) respevtively. Maximum fraction of sand by weight was found at stations III (81.60%) and II (76.78%). While the highest fraction of clay (22.58%) and silt (11.20%) was recorded in stations I. It was observed that benthic organism's abundance and distribution pattern were influenced with clay and silt fraction of the sediments as well as hydrological factors.