Colomerus vitis (Pagenstecher) is the economically most important pest within the genus Colomerus. In addition to direct damage feeding, it also transmits virus diseases in grapevine. Depending on the type of injury, three morphologically identical strains can be distinguished: erineum, bud, and leaf curl strain. Over the last two decades, the use of molecular genetic tools, has contributed significantly to our understanding of natural genetic variation and speciation within different strain of C. vitis. Several studies suggest that erineum and bud strain are distinct, closely related species, and indicate that C. vitis is a complex of cryptic species. The main objective of our research was to estimate the genetic divergence among the specimens of the erineum strain of C. vitis collected in the Balkans (Serbia, Greece, and Croatia) based on the COI gene and to combine it with all available data. The analysis of COI sequences in the 12 eriophyid populations obtained in this study showed high genetic variability. The presence of two groups corresponding to G1 and G5 was identified by the ML topologies of the phylogenetic tree