Field experiments were conducted at Regional Agricultural Research Station, Lam, Guntur to study the performance of Bt cotton under IPM, conventional control (CC) and unprotected conditions (check) for two consecutive seasons.  The incidence of aphids and whiteflies was low in IPM block compared to conventional control, while the incidence of leafhoppers was high under IPM. But the population of thrips was more or less similar.  The larval incidence of fruiting bodies damage of American and pink bollworm were slightly high in IPM block.  The activity of natural enemies under ecofriendly IPM was more compared to conventional control and check without presticidal application.  Though the yield was slightly less, the cost benefit ratio was high from IPM block (1:2.26) compared to conventional control (1:1.57) due to low cost of plant protection. Hence, 'Bt' cotton hybrids should be viewed as a foundation on which Integrated Pest Management (IPM) has to be built up to combat the pest problems for sustainable transgenic Bt cotton cultivation.