An oral ulcer occurs due to the erosion or loss of the upper mucosal layer, representing one of the mostcommonly encountered pathological conditions within the oral cavity. Typically, these lesions are painful and arepredominantly located on the inner surfaces of the lips and cheeks. Despite their distinct characteristics, all forms ofRecurrent aphthous stomatitis have a significant impact on quality of life and interfere with activities of daily living.Prednisolone Sodium Phosphate [PSP] is a corticosteroid drug used for allergies, inflammatory, autoimmune diseasesand in malignancies. PSP belongs to the Biopharmaceutics Classification System [BCS] class II and exhibits minimalsolubility in water. Therefore, nanotechnology is used for the preparation of formulation which has greater absorptionand bioavailability. The objective of the present research work is to formulate nanoparticles to improve solubility ofPrednisolone Sodium Phosphate [PSP] by using Emulsion- Solvent Evaporation method, and incorporate thesenanoparticles into fast dissolving mouth films for mouth ulcers. Further, we optimized PSP nanoparticles using designof experiments and evaluated optimized prednisolone nanoparticles for Particle Size, Zeta Potential, PolydispersityIndex, Scanning Electron Microscopy and X-Ray Diffraction. The oral fast dissolving films were evaluated on the basisof physical appearance, thickness, pH, weight disintegration time, folding endurance, and stability study. In-vitrodissolution studies demonstrated that more than 80% drug was released from fast- dissolving films. Incorporation ofPSP into nanoparticles resulted in increased solubility of PSP and oral fast dissolving films were utilized as a mediumto transport these nanoparticles for drug delivery applications which have better therapeutic efficiency andbioavailability with significantly higher drug release profile.