The present investigation on the population dynamics of thrips and bud necrosis disease on tomato crops (cv. Arka Vikas) was carried out during two consecutive crop growing seasons of Kharif, 2016 and 2017. Results revealed that there were two thrips species (Thrips palmi Karny and Scirtothrips dorsalis Hood) that occurred together at different crop growth stages and the population was high during the flowering stage (5.25 to 9.35 thrips/top three leaves), which later started to decline at crop maturity. The symptoms of bud necrosis disease started appearing after 3rd week of transplanting and increased gradually with necrosis symptoms on terminal buds followed by necrotic streaks on petioles and stems, leading to the complete collapse of the plants. The cumulative disease incidence was 43.80 % at the harvesting stage. Correlation analysis with the weather parameters indicated that rainfall and relative humidity exhibited a significant negative correlation with the thrips population and associated bud necrosis disease. While, the correlation of the miridbug, Nesidiocoris tenuis population, was linear with the thrips population and found throughout the cropping period.