Non-native fish invasions are among the greatest threats to freshwater ecosystems worldwide. In South China, the same climatic conditions that facilitate the culture of some non-native fishes may also support their invasive potential. We conducted systematic collections of fish in eight main rivers of South China, from 2016 to 2018, to investigate and analysis species composition and the distribution of non-native fishes. The data reveal that non-native fishes are widespread in the sampled rivers: of the 98,887 fish collected, 11,832 individuals representing 20 species were not native. Of the non-native fish species, 17 are used in aquaculture and 19 are native to the tropics; 13 are omnivores while other seven are predators. Based on dissimilarity of the non-native fish species distributions across the eight rivers, the different rivers could be divided into four assemblages. Geographical isolation and temperature were identified as affecting the distribution patterns of non-native fishes, thereby influencing fish species composition, species number, dominant species, and distribution variations in the South China rivers. Species composition of the non-native fishes in the rivers in this region are related to their introduction vector, compatibility with their native habitat, and trophic position. And their distribution pattern was mainly influenced by the geographical location and temperature.