Among the Coleoptera, case bearing is found in four related subfamilies of the Chrysomelidae, the so‐called Camptosomates: Clytrinae, Cryptocephalinae, Chlamisinae, and Lamprosomatinae (Böving and Craighead, 1931). Adults of case‐bearing chrysomelids feed on foliage of a variety of eudicots (Erber, 1988), but their larvae often show departures from strict phytophagy. Besides those with true herbivore larvae that feed on green plant parts and complete development on the host plant the larvae of most species live on the ground, in leaf litter, and feed on dry vegetable material and detritus (Erber, 1988; Brown and Funk, 2005). The larvae of some clytrine species live in ant nests (Erber, 1988; Brothers et al., 2000), but besides these mirmecophiles, many other clytrine larvae live in leaf litter and some few others on plants (Erber, 1988; Jolivet, 1988).The genus Physosmaragdina Medvedev, a clytrine genus with restricted distribution (Korea, Japan, China, Taiwan, South‐East Asia). In the Paleoarctic region 14 species have been reported; however, 10 were treated as synonymous, leaving 4 currently reported (Löbl and Smetana, 2010). Four Physosmaragdina species are distributed throughout south‐east Asia, from Korea to Japan, while on the other side, only one species were reported in Korea (Lee and An, 2001). Nothing is known about the immature stages of the genus Physosmaragdina.The purpose of this study is to describe, to illustrate the egg, egg‐case and first instar larva of P. nigrifrons (Hope), and remarks on their systematics.