The present study focuses on the phytochemical evaluation of an ethanolic extract derived from the leaves of Leucaena leucocephala. The extraction was performed using the Soxhlet method, followed by phytochemical analysis, compound separation, and isolation of bioactive constituents through Thin Layer Chromatography (TLC) and column chromatography. The isolated compound was subsequently characterized using various spectroscopic techniques, including IR, ¹H NMR, ¹³C NMR, and mass spectrometry. The ethanolic leaf extract was found to contain phytochemicals such as carbohydrates, alkaloids, saponins, tannins, flavonoids, lipids, fixed oils, and phenols. Spectroscopic analysis confirmed that the isolated compound, designated as LLQ, was quercetin. The presence of secondary metabolites in the extract also exhibited nootropic activity.