Little is known about the eastern Palaearctic species Anthrenus nipponensis, a member of the Palaearctic A. pimpinellae species complex. In the current study, a morphometric examination of specimens held in the Natural History Museum, London, is carried out. A. nipponensis
is larger and narrower than most other species belonging to the complex. The unusual shape of the antennal club is illustrated and discussed. The male genitalia are small but of comparable size to several other Anthrenus species relative to body length. The accuracy of published drawings
of A. nipponensis aedeagi is discussed. The literature is searched for records of A. nipponensis to produce a geographical and phenological distribution. The species is distributed across Japan, the Korean peninsula, north-eastern corner of China, and the south-eastern tip of
Russia. The adult flight season peaks during the second half of May. Details on the life history are included.