With China's opening up constantly deepens, the threats of invasive alien species unintentionally introduced into China are steadily on the increase to agriculture and forestry production. Eco-safety are further enlarged, however, few studies have examined the distribution patterns and trends of newly detected invasive alien species with respect to taxonomic categorization and origin in this country. Invasive species can impose serious damages to natural ecosystems and pose risks to regional economies and public health. Drainage basin ecosystems are more susceptible to biological invasions than other ecosystems because they are subjected to more frequent human disturbances. Only a small fraction of the alien species current research focuses is invasive species. Therefore, it is crucial to study the alien species in order to comprehend the mechanisms and control of biological invasion. This study was conducted in the Yiluo river basin, straddling Henan and Shaanxi Province (109°43'-113°10'E, 33°39'-34°54'N), ranging from 101 m to 1227 m. The Yiluo River is a major tributary of Yellow River in the south side of the middle reaches. The vegetation in the drainage basin ecosystem of Yiluo River has been heavily impacted by anthropogenic activities. In this research, we focused on the herb communities in different habitats formed by different disturbance types and intensity along different environmental gradients in the drainage area of Yiluo River. A field investigation was conducted in August and September of 2009, to acquire the alien species composition and distribution characteristics in different habitats, from three aspects, longitudinal gradient, transverse gradient and the different alien species among different three types of habitat distribution pattern of the herb species. Using community ecology techniques, 107 plots (20 m×20 m) were sampled. Each plot contains five 1 m×1 m quadrats located at the four corners and the center of the plot. We recorded all the herb species present in the quadrats including the alien species, as well as ecological conditions of the sampling sites. The results of this study show that: there were 27 alien herbaceous species belonging to 15 families in the Yiluo River basin. Compositae, Amaranthaceae and Leguminosae were the three main families, most of which were introduced by human intentionally. The distribution patterns of alien species individuals of occurrence of the alien species in distribution patterns differed significantly among the different habitats, the riparian habitat had the most alien species, while the woodland the farmland habitat had the least. Some of the alien species were widely distributed in all the three habitats, such as Conyza Canadensis, Aster subulatus and Amaranthus retroflexus. We used binomial regression to analysis the distribution patterns of the alien species along the longitudinal environmental gradient. The pattern showed slightly declining curve shaped, the least in the montanic regions in upper reaches of the river, then the hilly regions in middle reaches, and the most in the plains in the lower reaches. The upper reaches were largely covered with natural vegetation of light anthropogenic disturbance and relatively less alien species; therefore the distribution of a species was mainly constrained by its competence and dispersal ability, as well as habitat conditions. The intensively farmed lower reaches were dominated by agricultural ecosystems; species compositions were simple but involved the most alien species as a consequence of intense anthropogenic impact. The hilly transition zone of the middle reaches was under moderate anthropogenic disturbance, covered with mixed communities of natural and artificial plant species, with a relative high species diversity and more alien species. To sum up, the distribution patterns of herb alien species in the Yiluo river basin was strongly influenced by both anthropogenic activities and physical environment.