An investigation into the macrobenthos and physico-chemical parameters of Ogbese, River, Ondo State South West, Nigeria were investigated between February, 2022 and January, 2023. The research was to assess the health of the water body using macrobenthos as bio-indicator. Macrobenthos in the sediment were collected with the use of Van-veen grab and were identified with the help of standard identification key. Diversity of macrobenthos was estimated using Shannon-Wiener Diversity Index (H). Physico-chemical parameters were determined in-situ using probe meter. A total of 486 macrobenthos members belonging to one Phylum (Mollusca), two classes (Gastropoda and Bivalvia) and nine species were recorded throughout the study period. Lymnaea stagnalis had the highest relative abundance (61.73%) while Pisidium pseudophaerium and Valvata piscinalis had the least RA (0.41%). Highest (17.08%) relative abundance was observed in June and the least (2.91%) observed in December. The Shannon-Wiener’s diversity index indicated 1.29 and the Evenness (E) was 0.59. The results of the physico-chemical parameters were within the acceptable range except Dissolved oxygen which was lower than the acceptable limit for aquatic organism. The low diversity and abundance recorded were indicators of a poor water quality in Ogbese River. Therefore, there should be proper measures in managing various discharges that constitute pollutants in the water body.