Abstract: The forty terrestrial and aquatic Alternanthera Philoxeroides sampling plots were seted within the range of 21°N to 37°N in mainland China. According to WU Zhengyi's classification principles for the geographic division types of seed plant families and genera, the spatial differences of Alternanthera Philoxeroides community flora in heterogeneous habitats and the effects of latitude gradient on flora structures were examined. The results showed that: (1) A total of 178 plant species belonging to 149 genera and 51 families were recorded in terrestrial plots, and 104 plant species belonging to 90 genera and 43 families were recorded in aquatic plots. Meanwhile, many invasive plant species were recorded in Alternanthera Philoxeroides community and the frequent human activities accelerated their spreading. (2)Aquatic and terrestrial fauna all had obvious tropical characteristics. (3) From the family to the genus level, the floristic temperate elements increased. The main accompanying species were Digitaria, Echinochloa and Setariaweeds, they often formed the dominant species in subtropical or warm temperate zones. (4) With the decrease of latitude, the proportion of tropical distribution types of genera in flora increased, while the proportion of temperate distribution types decreased. In conclusion, tropical type components of families and genera in Alternanthera Philoxeroides flora had obvious advantages, while the temperate type components were less. Many invasive companion species originated from tropical zones had strong adaptability, and they occupied resources together with Alternanthera Philoxeroides. The heterogeneity of water and heat caused by latitude gradients constituted the effective driving force for evolution of invasive plant community flora.