To assess water quality of Qarun lake, forty-six of  lake water samples were collected during the period from 2014 to 2015.  Value of pH of Qarun lake ranged from 8.22 to 8.32. Value of alkalinity ranged from 9.8 to 33.4 ppm. EC_w values ranged from 26.5 to 40.99 dS.m^-1. Qarun lake contained the soluble cations in the following order: Na⁺> Ca²⁺> Mg²⁺> K⁺.  The SAR of the studied water in Qarun lake ranged from 274 to 400with a mean value of 337. The highest value of SAR occurred in season 2015 while the lowest one was in 2014. The hardiness value of Qarun lake ranged from 602 to 1567ppm. The COD values were higher than that of ECP501,2015. they ranged from 1168 to 1293 ppm. Different macro and micronutrients were more than the permissible limits. Water Quality Index (WQI) was applied using ten parameters of water quality (pH, Chloride, Chemical oxygen demand (COD), Iron (Fe), Phosphate (PO₄^-3), Chromium (Cr), Boron (B), Hardiness, Ammonium and Nitrate ). The results indicated that water quality of Qarun lake decayed from the year 2014 to 2015 and could be categorized into Unsuitable class. The effect of anthropogenic activities was obvious on some parameters such as nitrate and ammonium. Monitoring the water quality of Qaroun lake is necessary for proper management.