The aim of present research was to evaluate the toxicity of esfenvalerate on carbohydrate metabolism and macromolecular concentrations of 4th and 6th instar larvae of a stored grain pest, Trogoderma granarium. The LC50 values of esfenvalerate for 4th and 6th instar larvae of Phosphine and deltamethrin-susceptible population was 34.29 and 28.05ppm, respectively, while 39.30 and 32.67ppm were for the 4th and 6th instar larvae of Phosphine and deltamethrin-tolerant population, respectively. The sub lethal dose of esfenvalerate (LC20) significantly decreased the contents of glycogen, glucose, trehalose and free amino acid while total protein and total lipid contents, were significantly increased with reference to their control (untreated group). Among carbohydrate metabolizing enzymes, the activities of trehalase, amylase and invertase were significantly reduced after treatment with sub lethal dose of esfenvalerate as compared to control. The metabolic derangements induced by sub-lethal dose of esfenvalerate suggest that infestation caused by T. granarium in godowns could be overcome by calculating lethal dose of esfenvalerate.