Efficacies and economics of some new insecticides were evaluated for the management of major lepidopteran pests of tomato at Bidhan Chandra Krishi Viswavidyalaya, Kalyani, West Bengal during 2012–14. Three novel insecticides viz., pyridalyl 10 EC (56.25, 75, 112.5 and 150 g a. i./ha), indoxacarb 14.5 SC (56.25, 75, 112.5 and 150 g a. i./ha) and chlorfenapyr 10 SC (75, 100, 150 and 200 g a.i./ha) were applied twice with four doses along with two standard checks (chlorpyriphos 20 EC @ 350 g a. i./ha and triazophos 40 EC @ 350 g a. i./ha) and untreated control. Pooled results revealed that pyridalyl and indoxacarb @ 150 g a. i./ha were found to be very effective insecticides against Helicoverpa armigera (3.10 and 2.60% fruit damage) and Spodoptera litura (3.34 and 3.59% fruit damage) with 211.21 and 209.59 q/ha marketable yield, respectively. Results indicated that traditional insecticides such as triazophos and chlorpyriphos were most cost effective insecticides with 10.24 and 9.56 benefit: cost ratio, respectively, whereas pyridalyl and indoxacarb at lower doses showed cost efficiency for management of lepidopteran pests of tomato.