The zooplankton found in almost all water bodies is diverse. Because of the pivotal role of zooplankton in most aquatic ecosystems, Usethere is a constant need to explore the effect of stressors (such as physicochemical properties of freshwater) on their abundance Present paper deals with the study of monthly variations in the zooplankton population and their correlations with some physical characteristics of Kalinjur lake in Vellore district, Tamilnadu. From January 2021 to December 2021, Statistical analysis of data involves Pearson’s Correlation analysis and various diversity indices viz. Zooplankton diversity and population dynamics are controlled by numerous physicochemical factors. Zooplankton populations fluctuate with physicochemical factors. A total of 27 species of zooplankton from 4 major taxonomic groups were observed: Rotifera (9 species), Cladocera (7 species), Copepoda (6 species), and Ostracoda (5 species). Physico-chemical parameters of Kalinjur Lake revealed well-marked fluctuations with maxima and minima values of each parameter during specific seasons and zooplankton analysis revealed seasonal variations with an increase during winter and a fall during monsoon and summer seasons. Zooplankton populations were highest in December and January. The present investigation showed positive correlations with Rotifer parameters like calcium, nitrite, phosphate, chloride, and the Tidey test. In contrast, Turbidity, Electrical Conductivity, pH, Alkalinity, Total Hardness, Magnesium, Ammonia, Nitrite, Fluoride, Sulfate, BOD, and COD water showed negative correlations with the zooplankton population.