Mass production of virus was undertaken both at Agriculture Research Station, Gulbarga and University of Agricultural Sciences, Dharwad from 1993 to 1997 with a view to increase production and productivity of virus from laboratory reared as well as field collected larvae. Optimum inoculum dose required for third and fourth instar larvae was 10⁸ POB/ml to achieve quicker and higher mortality of larvae for virus Production. Among different instars of Helicoverpa armigera, the fourth instar larva was found ideal for virus production as it yielded higher quantity of virus per larva (2.81 x 10⁹  POB [Polydedral Occluded Bodies).The number of larvae required to produce one LE (6 x 10⁹ POB) of virus from field collected larvae was higher (2.97) than laboratory reared ones (2.14) since field collected larvae were of different size unlike the uniform stages in the laboratory roared ones. Economics of virus production revealed that cost of production of 100 LE (1 bottle) from laboratory reared larvae was Rs. 10200 being Rs, 25.40 more than field collected larvae (Rs. 76.30).