Nageen lake is very productive eutrophic urban lake of Kashmir valley. High concentration of dissolved nutrients like nitrates and total phosphorus promotes profuse algal and macrophytic growth. The study focuses on the impact of elevated temperature on macrofaunal assemblages. A composite Gerking frame box and grappler were used for sample collection. The effect of scorching heat was conspicuous as a result of mass fish kill in the affected area. It was found that the total invertebrate number reduced from 13 different families in reference site to just two families in the affected site. The Shannon index decreased from 1.8 (reference site) to 0.7 in the affected site. Also the dominance of some species decreased from 0.8 to 0.4, but the evenness increased from 0.5 to 1.1.