Abstract: Abstract: Invasion of natural ecosystems by exotic plant species is a major threat to biodiversity. The nature reserve contains a diversity of plant species. However, many exotic plant species have become established, potentially damaging the structure and function of native plant communities. The exotic plant species were investigated at selected sites and by walking through the Reserve (JFM), 1) Fifty six exotic plant species found in the JFM. They were mainly herbaceous plant species sporadically distributed in the park. The distribution of most of the alien plants (except Miscanthus floridulus) was consistent with human disturbance and together with the native plant species could be used as an available resource since they were not in competition with each other. 2) the exotic plants became established in four ways: introduced intentionally (31 species), natural invasion (15 species), uncertain, probably invasion (9 species), and introduced accidentally (1 species): the percentages were 55%, 27%, 16%, and 2%, respectively. 3) the frequency of invasive plants was positively correlated with human disturbance