This investigation of the biodiversity of copepods was carried out in the Hilla River. From January 2021 to December 2021, monthly samples of water and copepods were taken at three different locations in the river for this investigation. Water's temperature, turbidity, pH, salinity, dissolved oxygen, biological oxygen demand, total hardness, nitrate, and phosphate are some of the physical and chemical characteristics taken into account. A study was undertaken using biological indicators such the Shanon-Weiner index, Species Uniformity Index, and Species Richness Index. There were 24 copepod taxonomic units found. Copepoda had a maximum density of 1453 ind/m3 in April and a lowest density of 80 ind/m3 in February. The statistical study' findings revealed a statistically significant positive association between density, all of pH, BOD5, Nitrate, and Phosphate, as well as a statistically significant negative correlation with each of dissolved oxygen and total hardness. The Shanon-Weiner index recorded its greatest value in May, 3.33 bits/ind, and its lowest value in December, 0.08 bits/ind. The greatest value of the Species Uniformity Index (E) was 0.99 in March, while the lowest values of 0.1 were reported in July. Species homogeneity index and each of Turbidity have a substantial negative association and a strong positive connection, respectively. The Species Richness Index reached its greatest point in April (6.13), while it reached its lowest point in January (1.46). According to the statistical study, there is a strong positive association between Index values and a strong negative correlation with overall hardness.