Field experiment was conducted to estimate the crop loss due to stem fly during Kharif season of 2010-11 and 2011-12 at the Agricultural Research Station, Bailhongal, The seedling mortality, stem fly infestation and stem tunneling was recorded at 7, 15, 21, 30 and 35 Days After Sowing (DAS). The significantly lower seedling mortality, stem fly infestation and stem tunneling was recorded in T3 -seed dressing with thiamethoxam 70 WS @ 3.0 g/kg + foliar spray of thiamethoxam 25 WG @ 0.5 g/l at 20 DAS and has recorded significantly highest seed yield. The maximum cost benefit ratio was obtained from the treatment T4- (seed dressing with imidacloprid 70 WS @ 3.0 g/kg+ foliar spray of imidacloprid 17.8 SL @ 0.25ml/l at 20 DAS) recorded highest B:C (3.23).