The present study is to evaluate the effect of carbosulfan on the adult banana weevil Odoiporus longicollisOliv. and also to assessthe status of the acetylcholinesterase after treatment with sublethal doses of carbosulfan. Treatment with different concentrations of carbosulfan provided an LD50of 0.876µg/µl and LD90 of 1.117µg/µl at 24 hr duration of exposure. The levels of acetyl choline esterase assays were conducted in tissues like gut, reproductive organ, fat body and the whole insect and quantified at various sublethal concentrations against different time duration of exposure. The adult insects were treated with 10%, 50% and 80% of lethal dose (LC50) for 24 hr,48 hr. and 72 hr. The results obtained in the present investigation clearly indicate that various concentrations of the carbosufan have produced intensive toxic effect at tissue level in Odoiporus longicollis.