Naproxen Sodium (NS) is effective for pain and inflammation but can cause gastrointestinal irritation and skin sensitivity. Incorporating Vitex Negundo oil (VN oil), known for its anti-inflammatory and soothing properties, with NS enhances therapeutic efficacy and reduces skin irritation. VN oil also contributes to a more controlled and sustained drug release by mitigating the initial burst effect, improving the overall release profile of the formulation. This study focuses on formulating and evaluating solid lipid nanoparticles (SLN) containing Naproxen Sodium and Vitex Negundo oil. SLNs were prepared using the hot homogenization technique with varying concentrations of lipids, surfactants, and stabilizers.