Agrochemicals that are used as pesticides are not highly selective but are generally toxic non-target species, including man, and other desirable forms of life that co-inhabits the environment. Pesticide is bioavailable; there will be uptake in the organism and interaction with receptor site, which may evoke measurable biological effects. Profenofos was used as pesticide widely in India. Protein content in foot, mantle and gills of freshwater bivalve Lamellidens corrianus exposed to acute treatment of Profenofos were studied in the present investigation.