Species composition and abundance of myctophid fish were analysed using the fish by-catch samples collected by scientific observers on board Japanese commercial krill fishing vessels in the area north and northwest of South Georgia, Antarctica, during austral winters from 2002 to 2008. A total of 10 myctophid species were identified in the by-catch samples, among which Krefftichthys anderssoni, Gymnoscopelus nicholsi and Protomyctophum choriodon were abundant. Different life stages of K. anderssoni and G. nicholsi from larvae to adults were found, suggesting that these species may have their nursery ground around South Georgia. Electrona antarctica was not a major component of the recent mesopelagic ichthyofauna in this area, although this species used to be dominant in the Antarctic coastal waters. In contrast, P. choriodon, which is known as a south temperate species, became dominant in recent samples. Additionally, the size distribution of P. choriodon was unimodal, indicating that individuals in the samples belonged to the same size group and probably migrated from the population in warmer northern areas.