This study aims to prepper stable thermodynamically dilutable nanoemulsion formulation of Beauveria bassiana with the lowest surfactant concentration that could improve its solubility stability. Formulations were prepared from oil in the water nanoemulsion region of phase diagrams subjected to thermodynamic stability tests. We found propanetriol was the highest germination rate at 5% and 10% concentration, 46.66 and 53.33%, respectively. Castor oil achieved a 43.00 germination rate at 1%. Tween 80 gave 54.33 % germination rate at 10%. While Tween 20 showed a 48 % germination rate at 5%. At the concentration, 1% Term 1284 gave 43.33% rate germination. Nanoemulsion composed of propanetriol and nonionic surfactants, with a mean particle size ranging from 25.08 to 75.35 nm, was formulated for various concentrations of the oils and surfactants. Water in oil emulsion was prepared using propanetriol oil, Tween 20, Tween 80, Term 1284, and water. Nanoemulsion of 25.08, 33.75, and 75.35 nm size was obtained at a 45: 15 % ratio of oil and surfactant, and it was found to be stable. The larger droplet size 75.35 nm of formulation Tween 20 and the smaller size was 25.08 nm in the formulation of Term 1284. The higher viscosity value was 16 mPas of formulation Tween 80, and the lowest value was 7.80 in the formulation of Term 1284. To demonstrate the possible employment of these systems, they were used to formulate a nanoformulation pesticide.