Abstarct: Fumigation with methyl bromide and phosphine is the usual method to control infestations of post harvest insects. pest resistance and the increased demand for organic food, food manufacturers and scientists are looking for new ways to control insects in stored commodities. Entomopathogenic fungi have been shown to be effective biological control agents against several insect pests. The aim of the current study was to investigate pathogenecity of three isolates of B.bassiana on the Indian Meal Moth and also, to select the best formulation which is more effective. In this study, pathogenicity of three isolates (SA1,SA2 and SAVA) of B.bassiana was investigated against larva of The Indian Meal Moth. The dipping method was used in all bioassays. Experiments was performed at completely randomized design using the third instar larvae. The fungal concentrations used for bioassays were consisted of 10^4, 10^5,10^6 10^7 and108 conidia /ml. The control insects are treated using sterile distilled water containing 0/05% Tween 80. Results showed that the highest percent mortality of larva belonged to SA2 isolate of B.bassiana and there was significantly difference in mortality percentages between the other isolates used The mortality rate was increased with increasing in conidial concentrations in all experiments. Estimated LC50 for each isolates (SA1, SA2 and SAVA) on third instar larvae were 4/4×10^6 , 1/03×10^6 and 3/92×10^6 10^4 conidia/ml, respectively. In addition to virulence and higher mortality rate, the isolate SA2 has a higher radial growth and spore production. The characteristics of this isolate, have led to its selection as a desirable isolate for subsequent experiments. Six formulations of B.bassiana (three oil formulations and three wettable powder formulations) were prepared. The formulations were evaluated against third instar larvae of P.interpunctella. Each formulation was prepared at a concentrations of 1×10^7 conidia /ml. Among the oil formulations the highest larva mortality was observed in rapeseed oil formulation with 96±3/33 percent mortality and the lowest was the sesame formulation with 75±0/9 percen mortality. Sunflower oil formulation also showed 92±3/86 percent mortality. Among the wettable powder (WP) formulations, kaolin formulation recorded highest virulence with 95±4/16 percent mortality and was recognized as the best formulation. Least virulence was observed in talc formulation with 73±1/16 percent mortality. Wheat flour formulation also showed 82±3/90 percent mortality.