Using zooplankton as bioindicators, this study evaluates the ecological condition of the Euphrates River in Iraq's Babylon Province. Site 1 (North Hillah, next to the old Babylon ruins), Site 2 (Hillah city center), Site 3 (South Hillah, close to Al-Mahaweel), and Site 4 (near Al-Kifl town) were the four monitoring locations chosen along the river. The highest and lowest averages of the measured physical and chemical factors indicate temperature (25.1°-29.4°), pH (7.2-7.9), electrical conductivity (EC) (940 µS/cm-1241µS/cm), total dissolved solids TDS (591 mg/L-789mg/L), dissolved oxygen (DO) (5.6 mg/ l-7.1 mg/L), biological oxygen demand (BOD5) (2.4mg/L-4.2 mg/L), nitrate (1.3 mg/L–3.2 mg/L), nitrite (0.04 mg/L–0.13 mg/L), phosphate (0.3 mg/L-0.6 mg/L), turbitity (5.5 NTU-9NTU), calcium (45 mg/L-60 mg/L), magnesium (20 mg/L–35 mg/L), total hardness (150 mg/L–210 mg/L) that was the seasonal data for the year. Zooplankton communities were collected include amphipoda (52 ind/l-116 ind/L), cladocera (68 ind/l-114 ind/L), cyclopodia (154 ind/L-350 ind/L), macrobrachium nipponense (224 ind/L-350 ind/L), decapoda (Crab) (54 ind/L-112ind/L), Naplus larvae (16 ind/L-76 ind/L), and analyzed for diversity indices recorded including shannon-Wiener index (1,499-1.719), species richness according to 6 in all locations species evenness between (0.837-0.96). The Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) was applied to evaluate the water quality and he recorded between (45.16-72.42). According to the study, the water quality of babylon's euphrates river ranges from poor to fair. Although they varied by location and season, the physical, and chemical conditions were generally within tolerable bounds. There were six major groupings of zooplankton, indicating a moderate level of diversity. Aquatic life is generally supported by the river, although certain locations exhibit indications of ecological stress.
