This manuscript reports a chemical investigation involving reverse-phase semipreparative HPLC-based isolation, followed by mass spectrometric and NMR-based characterization of three endophytic fungi recovered from Albizia lebbeck (L.) Benth. The study yielded two compounds (1-2) from ALE-75 (Sacharicola bicolor), three (3-5) from ALE-85 (Aspergillus pseudoglaucus), and one (6) from ALE-121 (Aspergillus eurotium). The extract from Aspergillus pseudoglaucus exhibited antioxidant potential (IC₅₀ = 11.92 µg/mL in DPPH assay) and moderate cytotoxicity against lung (A549, IC₅₀ = 35 µg/ml), colon (HCT-116, IC₅₀ value of 45.4 µg/ml), and breast (T47D, IC₅₀ value of 2.8 µg/ml) cancer cells, with growth inhibition of 89%, 77%, and 74% at 100 µg/ml. ALE-121 extract showed strong cytotoxicity against lung (A549, IC₅₀ = 11.2 µg/ml), colon (HCT-116, IC₅₀ = 12.5 µg/ml) and breast (T47D, IC₅₀ = 15 µg/ml) cancer cells, with inhibition rates of 85%, 84%, and 75% at 100 µg/ml. Compound 6 (Austrocortinin) showed strong cytotoxicity against these cancer lines, with inhibition rates of 89%, 87%, and 67% at 10 µg/ml. Compound 1 was initially identified through the fermentation process of the endophytic fungus Coriolopsis sp. J5, which was isolated from the mangrove Ceriops tagal and compound 2 in Penicillium chrysogenum LF066 from the marine sponge Tethya aurantium. Compounds 3-5, originally found in Chaetomium globosum and Aspergillus flavus, whereas Compound 6 was initially discovered in the Australian Cortinarius toadstool. Although these compounds have been identified previously, this is the first instance of their reporting in the aforementioned endophytic fungi isolated from Albizia lebbeck.