The negative effect of chemical insecticides has ted to the efforts in tinding altemative strategies for biological pest control. Mycoinsecticide is one ofthe biological pesticides. which is among the most interesting agents of insect control. lt is well known that entomopathogenic fungi can kill insects.There are only few commercial products, which are produced on large scale for several years. Beauveria bassiana is one of the entomopathogenic fungus commonly used as a biocontrol agent for pests of crops. This fungus can be isolated from soil, plant materials or insect cadavers.This thesis consist of two papers, entitled : Isolation, identification and screening of indigenous entomopathogenic fungus B. bassiana from Brebes, Central of Java, and Optimization of mycoinsecticide production of indigenous B. bassiana using rice tlour as a substrate. The aims of these research are to isolate, identify and screen indigenous entomopathogenic fungus B. bassiana from Brebes, Central of Java and to assess the optimization of mycoinsecticide fermentation of indigenous B. bassiana using rice flour as the substrate through solid substrate fermentation (SSF) technique.