[Objectives] During fish expeditions to the Red River Basin conducted in 2023 and to the Salween River Basin in 2025, the authors discovered a freshwater fish species Danio roseus, which had not been recorded from these basins both in Hekou, Honghe Hani and Yi Autonomous Prefecture and Gengma Dai and Wa Autonomous County, Lincang City in Yunnan Province. [Methods] This study employed an integrative approach combining morphological and molecular analyses to characterize the collected specimens. Morphological identification was conducted by documenting diagnostic anatomical features and cross-referencing taxonomic descriptions from established Danionidae literature. For molecular phylogenetic analysis, PhyloSuite 1.2.2 was used to construct a Bayesian inference tree based on mitochondrial cytochrome oxidase I (COI) gene sequences. All novel COI sequences generated in this study have been deposited in the GenBank (accession numbers provided in Table 1), while comparative sequences were retrieved from existing entries in the same repository. Morphological and molecular phylogenetic comparisons were conducted between D. roseus from the Lancangjiang River in China, D. roseus from the Mekong River in Thailand, D. albolineatus from the Irrawaddy River in China, and D. albolineatus from Myanmar. [Results]The specimens of Danio from the Red River, Salween River, Irrawaddy River, and Lancangjiang River in China were shown to be the same species. D. roseus, the species with distribution in the four rivers, was described, with morphological photos (Fig. 1) and morphological data (Table 2) for identification and phylogenetic analysis (Fig. 2) being provided and the distribution being redefined. In addition, the distinguishing between D. albolineatus and D. roseus was proposed (Fig. 3). [Conclusion] D. roseus is the first record of Danio in the Red River Basin and the first record in the Salween River Basin. Long-term misidentification of D. roseus in the Irrawaddy River, Yunnan Province as D. albolineatus is rectified.