Penicillium is a versatile ascomyceteous fungi. It causes opportunistic infections and putrefaction of foods. Penicillium species are known to produce more than 900 documented bioactive compounds. Furthermore, important pharmaceutical agents, namely, penicillins and compactin, have been isolated from Penicillium spp. We have reported that this fungus also produces valuable secondary metabolites, such as JBIR-12, JBIR-27 and JBIR-28. Therefore, we further screened for novel secondary metabolites from culture broths of Penicillium species. In this paper, we report the fermentation, isolation and structural determination of a new secondary metabolite, JBIR-54 (1), in addition to the taxonomy of the producing microorganism.