This study aimed to evaluate the antioxidant, antidiabetic, and anticholinesterase activities of Buchanania lanzan Spreng seeds. The therapeutic significance of phytochemicals, minerals, and nutrition were quantified. Hydroalcohol-extract (HABL) possessed the highest phenol contents demonstrated superior inhibitory potential against oxidants in DPPH, CAP-e, and imparted total antioxidant capacity in ORAC test. HABL exhibited mixed-competitive inhibition against α-amylase and α-glucosidase. HABL exhibited mixed-competitive and competitive inhibition against acetyl-, and butyryl-cholinesterase. Seeds were a rich source of minerals, amino acids, protein, carbohydrates, volatile oil, and energy content. Reported Vit B3 and B6 in seeds were responsible for brain function, and neurotransmitter-synthesis. HPLC quantified phenols (gallic acid, chlorogenic acid, caffeic acid, rutin, and quercetin), and GC-MS identified (Catechol, 2-Hydroxy-5-methylbenzaldehyde, Hexadecanoic acid, methyl ester, n-Hexadecanoic acid, Hexadecanoic acid, ethyl ester, 8-Octadecenoic acid, methyl ester, 9,12-Octadecadienoic acid, ethyl ester, (E)-9-Octadecenoic acid ethyl ester, Heptadecanoic acid, 15- methyl-, ethyl ester, Hexadecanoic acid, 2-hydroxy-1-(hydroxymethyl)ethyl ester, 9-Octadecenoic acid (Z)-, 2-hydroxy-1-(hydroxymethyl)ethyl, and β-Sitosterol) in HABL exhibited antioxidant, antidiabetic, and anticholinesterase activities. B. lanzan seeds are given adequate attention for making medicines and dietary supplements in the pharmaceutical and nutraceutical industries.