The family Cyprinidae is one of the largest families of fish in the world and a well-known component of the East Asian freshwater fish fauna The majority of research on animals has used single mitochondrial DNA genes to assess population or law-level taxonomic relationships. Phylogenetic relationships between Romanian cyprinids (Teleostei: Cypriniformes: Cyprinidae) from the Danube river were investigated comparing cox2 mitochondrial gene sequences from ten species (Barbus barbus, Arischthys nobilis Hypophthalmichthys molitrix, Scardinius erytrophtalmus, Tinca tinca, Rutilus rutilus, Cyprinus carpio, Abramis brama, Carassius auratus gibelio, Carassius carassius). Scardinius erytrophtalmus was newly sequenced Phylogenetic analysis indicated that there are two principal lineages in Cyprinidae: cyprinine and leuciscine. The cyprinine group includes the Cyprinus, Carassius, Barbus and Tinca genera. The taxonomic position of genus Tinca is controversial, because the neighbor-joining and maximum parsimony analysis place it in the cyprinine group alongside with the Carassius genus and in the maximum likelihood tree it appears as a paraphyletic group with the leuciscine lineage. The leuciscine group is divided into two clades. One includes the genera Abramis, Scardinius and Rutilus and the other includes the Arischthys and Hypophthalmichthys species which originated from Fast Asia. Cobitis danubialis was used as an outgroup species.