Abstract: To determine time trends in mortality for various insecticides, which are being used against cotton pests, the fourth instar larvae of Spodoptera litura was collected from Muzaffar Garh and tested for pyrethroids, organophosphate and new chemistry insecticides. The efficacy of the insecticides was examined by time-oriented mortality at LC50, through leaf-dip bioassays in the laboratory. In sodium channel agonists, endosulfan was the most efficient insecticide. The cholinesterase inhibitors tested, chlorpyrifos showed high efficiency while phoxim performed better in time-oriented mortality. Emamectin benzoate proved to be the most efficient insecticide in new chemistry insecticides tested. Spinosad and indoxacarb had almost similar LC50 and LT50 values. The least effective insecticide found was abamectin. The results are discussed in relation to Integrated Pest Management (IPM).