Abstract:In order to understand the situation of invasive alien plants in farmland ecosystems, the invasive plants in 9 cities of Fujian Province were investigated by field investigation, and the species composition, origin, life form, distribution pattern and type as well as invasiveness were analyzed. The results showed that there were a total of 79 species of invasive plants, belonging to 30 families, 65 genera, in farmland ecosystems in Fujian Province. There were 22 species of Asteraceae, which was the most abundance accounting for 27.85% to total species, followed by 7 species in Amaranthaceae, each 5 species in Leguminosae, Gramineae, Convolvulaceae and Euphorbiaceae. From life form, 68 species of invasive plants were herbaceous, accounting for 86.08% to total species. From the origin of invasive plants, the number of species native to America was the highest, accounting for 70.24% of total species. The alien invasive plants in Fujian were classified as malignant invasive species (grade 1) with 22 species in 10 families, and 22 species as serious invasion (grade 2), 9 species as local invasion (grade 3), 18 species as general invasion (grade 4) and 8 species to be observed (grade 5). In addition, the number of alien invasive plants at malignant and severe grade was high, accounting about 55.70% of total species. From distribution pattern and type, the number of invasive plants in farmland ecosystems of Fuzhou was the most with 52 species. Among different types of farmland, the number of invasive plants in dry land was the largest, with 78 species. There were 13 and 11 species in all regional distribution type, respectively according to the distribution region and the farmland type. There were many invasive plants in farmland ecosystem in Fujian province, which are widely distributed and diverse in origin. Therefore, the dynamic monitoring and prevention of alien invasive plants should be strengthened to protect biodiversity and ecological security.