This study was conducted to investigate the plant community structure and to propose ecological management planning for the urban forest on Sungdongku, Joongku and Yongsanku in Seoul. Field survey was excuted October 1991 and the results were as follows. Robinia pseudoacasia community covered 61.1% and Populus x albaglandulosa covered 3.8% of survey site II and survey site was covered by the deciduous-broad leaf mixtured forest. According to the human impact and inappropriate management impact, survey area was divided into five forest community. As for the analysis of plant community structure which was classified into five forest community, the importance values, ecological diversity, number of species, number of individuals, basal area and crown coverage of the native plant community showed relatively higher than community that vegetation deterioration degree by the human impact showed seriously. In landscape forest of Mt. Daehyun, it showed problems for the planting method and the soil condition. So it was proposed to management guide, vegetation restoration and soil management through ecological management planning based on above results.