Kamchatka is a remote volcanic peninsula in the sub-arctic Far East of Russia. Its myrmecofauna has been scientifically addressed several times. However, previous species lists are contradictory in part and a modern study seems to be lacking. Based on literature review, I conclude that 12 species and 4 genera (Camponotus, Formica, Leptothorax and Myrmica) of ants may be native to Kamchatka. Of those, 9 were found in the field, 3 having a Holarctic, 3 a trans-Palearctic and 3 an East Palearctic distribution. Most species diversity was found at mid-elevations, in pine shrubs and mixed forests, while deciduous forests and open habitats at lower altitudes were surprisingly species poor. DNA-barcoding was performed for 57 specimens/9 species. Genetic diversity (COI) was low for 8/9 species, with the exception of Leptothorax acervorum, for which all samples were of a different haplotype and 2 haplogroups were identified. For the encountered Holarctic and trans-Palearctic species, closely related haplotypes (<0.7% raw distance) occur in Europe and/or North America. Some Formica ants were morphologically atypical, with workers partially resembling those of F. fusca, while gynes identified as F. lemani. Morphometric analysis and DNA-barcoding suggested that all these specimens belong to a single species, F. lemani. Standard images for all specimens and an illustrated key to the worker caste are provided.