[Objectives] This paper reported a new geographical record of the genus Dactylogyrus on the gills of Rutilus rutilus lacustris from Irtysh River (Haba River section) investigation of fish parasites in July 2021. [Methods] Based on careful morphological comparison with those relevant species, significant differences in the copulatory complex and the opisthaptor of the parasite were observed. [Results] In copulatory complex, the parasite has an “8” structure at the base of the tube. Then the diameter of the tube is uniform. The tube extended in a curved shape resembling “6”. About the opisthaptor, the parasite’s inner root of anchor was longer than the length of the outer root, with seven pairs of small marginal hooks. And this Dactylogyrus hasthe “一”-shaped dorsal bar and a butterfly-shaped ventral bar (Fig. 1, 2). The characteristic structure of this parasite differs from other Dactylogyrus that parasitic Rutilus rutiluslacustris in China (Appendix 2). The parasite in this study is small. Compared with D. caballeroi, the morphology of the opisthaptor of the two insects was most similar, but the morphology of the copulatory complex of the two was very different. In comparison with the rest of Dactylogyrus spp, the parasite has a butterfly-shaped ventral bar, D. rarissimus has an inverted “T”-shaped ventral bar, and D. rutili has a “十”-shaped ventral bar. However, D. sphyrna and D. varius have no ventral bar. In the dorsal bar morphology, D. crucifer showed a “一”-shape, while the dorsal bar of D. varius had a “V” shape. After comparison, the morphology of the parasite was highly similar to that of D. crucifer, recorded in Russia. The Bayesian inference and maximum likelihood trees constructed based on the 28S rDNA gene fragments showed that the D. crucifer in this study clustered with D. crucifer in Czech Republic (100/100) (Fig. 3). [Conclusion] The results were combined and the insect was identified as D. crucifer Wagener, 1857, a new record species of Dactylogyrus in China.