The grasshoppers and locusts are considered as pests to many agricultural crops, and the increased concerns over the deleterious environmental and health effects of using chemical insecticides to control their outbreaks. Like other microbial agents Entomopathogenic fungi are also responsible for suppression of grasshopper and locust population. During the present study an attempt has been made to investigate the lethal effect of entomopathogenic fungi eg: (Aspergillus, Metarhizium and Beauveria) on many grasshoppers’ species under laboratory conditions. Prepared medium of these bio-pesticides was sprayed on different species/stages of Acridinae, Calliptaminae and Gomphocerinae. Large numbers of species including their all developmental stages which were treated with this bio-pesticide showed significant suppression effect. Further, it was observed that insect’s undergone very interesting behavioral modification after the infection of pathogen and insect population decline rapidly in laboratory. However, improved prediction and monitoring are needed to facilitate the use of bio-pesticides and other IPM techniques against these pests. Beside this, in this paper we have also documented: how biological control option could be incorporated into integrated pest management (IPM) strategies and what future and development work is necessary to implement such IPM strategies in Pakistan.