Three new lycopodium alkaloids, huperserramines A-C (1 - 3, resp.), along with 15 known ones, lycopodine-6α,11α-diol (4), lycoposerramine H (5), lycoposerramine I (6), lycopodine-6α-ol (7), lycoposerramineM(8), diphaladine A (9), lycoposerramine K (10), lycoposerramineW(11), huperzine M (12), luciduline (13), phlegmariuine N (14), huperzine A (15), huperzine B (16), lycodine (17), and lycoposerramine R (18), were isolated from the whole plant of Huperzia serrata. Their structures were established by spectroscopic methods, including 2D-NMR and MS analyses. All the isolates were evaluated for their inhibitory effects on acetylcholinesterase (AChE) and α-glucosidase. As a result, lycopodine-6α,11α-diol (4) exhibited more potent α-glucosidase inhibitory activity (IC50 148±5.5 μm) than the positive control acarbose (IC50 376.3±2.7 μm). © 2014 Verlag Helvetica Chimica Acta AG, Zürich.