The River Henwal is ecological important tributary of River Ganga and drain in the western part of Uttarakhand, India. As it flows through the commercial and city areas, the large amount of wastages discharged inform of domestic and commercial wastewater and other activities like clothes washing and bathing using detergent and soaps. Also due to its aesthetic importance large number of tourism activities is also affecting the water body from its originating point itself. In the present study, water quality of the river is assessed at 4 sampling locations including one control site, with the comprehensive pollution index (CPI) by considering the 11 physiochemical parameters like conductivity, turbidity, total solids (TS), dissolved oxygen (DO), free CO2, total alkalinity (TA), total hardness (TH), Ca hardness, Mg hardness, Cl -, phosphate and eight heavy metals (Zn, Pb, Mn, Fe, Cu, Al, Cd and Mg). Besides this, Simpson's diversity index (D), Shannon-Weaver index (H) and Taxon Evenness (E) are also calculated to get the diversity of planktons and their impact on water quality of river. The CPI was found to be 1.88-4.37 (CPI > 2), which is indicates that water quality of River Henwal is slightly and severely polluted too on different sites. The high value of Simpson, Shannon-Weiner index and group evenness was 1.60, 4.88 and 0.47 respectively. Therefore, in this study the water quality was found unfit for drinking purposes and requires proper treatment before use.