Club moss (Lycopodiaceae) is known to be a rich source of Lycopodium alkaloids possessing unique heterocyclic ring systems such as C16N, C16N2, and C27N3, which have attracted great interest from biogenetic, synthetic, and biological points of view. In our continuing efforts to find biogenetically interesting and structurally unique Lycopodium alkaloids, we have isolated a number of new Lycopodium alkaloids possessing complex fused-cyclic skeletons, which have attracted as challenging targets for total synthesis. Further investigations of extracts of newly collected Lycopodium complanatum resulted in the isolation of a new Lycopodium alkaloid, lycopladine H (1), possessing a novel fused-tetracyclic ring system consisting of an azocane ring connected to a [2,2,2]-bicyclooctane ring and a 3-piperidone ring. In this Letter, we describe the isolation and structure elucidation of 1. Lycopladine H (1) is an unprecedented C16N-type Lycopodium alkaloid possessing a novel fused-tetracyclic ring system consisting of an azocane ring (C-9–C-14, C-5, and N-1) fused to a [2,2,2] bicyclooctane ring and a 3-piperidone ring. Lycopladine H (1) did not show cytotoxicity against L1210 murine leukemia and KB human epidermoid carcinoma cells (IC50 >10 lg/ml) in vitro.