Medicinal plants are the main source of active chemical constituents responsible for curing or mitigating various ailments. To discover new, safe, and effective drug candidates the isolation and screening of natural products are essential. In the current research work, lapachol was isolated from Fernandoa adenophylla, which was evaluated for anti-inflammatory effect followed by molecular docking. The isolated compound was tested for anti-inflammatory effects using in vitro (HRBC assay) and in vivo (xylene-induced ear edema) experimental models. Various concentrations of lapachol demonstrated anti-inflammatory effects with a percent potential of 77.96 at 100 μM. Different concentrations of Lapachol demonstrated a dose-dependent anti-edematous effect with a maximum percent effect of 77.9 % at a higher dose. The histopathological study revealed that the application of xylene led to a significant increase in ear thickness, along with clear signs of ear edema and infiltration of inflammatory cells, as well as epidermal hyperplasia of the dermis when compared to the control group. However, treatment with the investigated compound showed a significant reduction in ear thickness and pathological differences comparable to those observed in the group treated with diclofenac. Density functional theory calculations are accomplished to gain insight into structural and spectroscopic properties. Geometry optimization, FMO, and MEP analyses are performed. Overall, the molecular docking results indicate that lapachol has potential as a COX inhibitor by binding to the active sites of both COX-1 and COX-2 enzymes.