Aquatic macro invertebrate are used in fresh water quality assessment to identify the environmental stress from a variety of anthropogenic disturbances. They also play a significant role in the food chain of an ecosystem. Monthly survey of macrobenthic community diversity and water quality assessment was done from Dec. 2015 to Nov. 2016 in Thippagondanahally reservoir. Three phylums Arthropoda, Mollusca and Annelida were reported. Arthropoda was the most dominant group in all seasons.