A field experiment was conducted at K. N. K. College of Horticulture, J. N. K. V. v., Mandsaur (M. P.) under AICRP on Medicinal and Aromatic Plants during winter (rabi) seasons of 1995-96 and 1996-97 to find out the suitable weed management practices in opium poppy. Field studies revealed that pre-emergence (PE) application of isoproturon coupled with hand weeding (HW) at 30 days after sowing (DAS) proved more effective in reducing weed population and weed biomass and in increasing yield and attributes of opium poppy than isoproturon applied as pre-emergence alone. Isoproturon at 375 g ha" PE+HW at 30 DAS and isoproturon at 500 g ha· 1 PE+HW at 30 DAS were as effective as weed-free check in reducing density and biomass of weeds and in increasing yield attributing characters viz., capsules planrl, capsule diameter and capsule length and latex, seed and husk yields and net profit. Maximum weed mortality (WM, 92.1%) with latex yield (74.6 kg ha"), seed yield (711.3 kg hal), husk yield (744.3 kg ha") and net profit (Rs. 42990 ha") were recorded under weed-free check and it was closely followed by isoproturon at 375 g ha" PE+HW at 30 DAS and isoproturon at 500 g ha-' PE+HW at 30 DAS, where 83.6 and 90.1% WM, 70.1 and 62.8 kg ha-' latex yield, 664.3 and 605.3 kg ha-' seed yield, 677.8 and 593.9 kg ha-' husk yield and Rs. 42812 and 36154 ha- ' net profit were recorded, respectively. Morphine content of opium remained unaffected due to use of isoproturon in opium poppy. Uncontrolled weed growth caused 57.4% mean loss in latex (50.8%), seed (61.5%) and husk (59.8%) yields. Higher dose of isoproturon at 500 g ha-' PE caused 22.5% phytotoxicity on opium crop.