An increase in urbanization and industrial activities and higher exploitation of cultivable land has brought about a huge increase in the quantity of discharges and wide diversification in types of pollutants that reach rivers and other aquatic environments. Mollusca are one of the most diverse groups of animals on the planet. Fresh water snails have been used frequently as bioindicator organisms. The use of fresh water mussels for biomonitoring purpose is mostly a recent phenomenon. Fresh water snail Lymnaea acuminata is abundantly found in low lying submerged water logged areas. The snail L. acuminata breeds round the year and they are very sensitive to changes in the quality of water. Effect of seasonal changes on the inhibition of key enzymes-acetylcholinesterase (AChE) and alkaline phosphatase (ALP) in the nervous tissue of snail L. acuminata. This study shows that variant abiotic environmental factors can significantly alter the activity of AChE and ALP activity. Conclusively, the snail L. acuminata and the activity of AChE/ALP in the nervous tissue of snail can be used as bioindicator and biomarker for the prediction of water quality.