Pinguicula ramosa Miyoshi (Lentibulariaceae), endemic to Japan, is one of the most unique Pinguicula species often having a branched pedicel. Ecologically it occurs on cliffs formed by tuffs, porous volcanic rocks, which is also unusual as many Pinguicula species can be more commonly found on calcareous soils or serpentinite rocks. However, little attention has been previously given to this tiny endangered species with very few references in the literature outside of Japan, or even in there. To reveal the species, observations of the plants in situ, herbarium specimen examinations, and review of the literature have been performed. In addition, comparisons with morphologically and phylogenetically closely related species, P. variegata Turcz. and P. villosa L., will be summarized. This work is a botanical review overall P. ramosa discussing its morphology, distribution, taxonomy, ecology, history, conservation, and other scientific matters.