The damage caused by insect pests is one of the major reasons of low productivity. Sachan et al. (1994) have reported that pigeonpea is attacked by nearly 250 species of insect worldwide belonging to 8 orders and 61 families though relatively few cause serious yield losses. The key pests of long duration pigeonpea include gram pod borer Helicoverpa armigera (Hub.), are potential pests and occasionally cause significant grain yield losses in long duration pigeonpea. Keeping in view the above facts and in order to minimize the losses caused by the insect pests in long duration pigeonpea, the following investigation was carried out in the Objectives 1. To determine the incidence pattern and population build up of Major insect pest of pigeon pea at Varanasi. 2. Screening of some promising line of pigeon pea, against various 3. To estimate the losses cause by major insect pest.