In a two year study conducted at RCA, MPUAT Udaipur on Bt cotton revealed that imidacloprid 17.8 SL (200 ml/ha) significantly reduced the populations of aphids (up to 84.87 %) and whiteflies (up to73.28 %) after first spray; whereas, fipronil 70 WG (100 g/ha) was significantly effective in reducing the populations of leafhoppers (up to78.06 %) and thrips (up to 80.71 %); likewise, after the second spray, imidacloprid 17.8 SL (200 ml/ha) showed a significant reduction in the population of aphids (up to 74.97 %), leaf hoppers (up to 77.84 %), thrips (up to 72.18 %) and whiteflies (up to 74.44 %). Among bio-pesticides neem oil (3%) was more effective in reducing the sucking pest population. Second spray of imidacloprid 17.8 SL (200 ml/ ha) and thiamethoxam 25 WG (100 g/ ha) significantly reduced the population of aphids, leaf hoppers, thrips and whiteflies. Neem leaf extract (5%) was least effective and showed the minimum per cent population reduction after both sprays. During both the sprays, among treatments the maximum number of natural enemies (coccinellids and spiders) population was observed in plots treated with neem leaf extract and neem oil than in insecticide treated plots, while minimum numbers were recorded in plots treated with thiamethoxam.