Green space and plant diversity and structure have been undergoing significant changes in characteristics and trends along the urban-rural ecotone in Beijing due to the process of urbanization. Analyzing these changes is necessary for the protection of plant diversity and the integration of green construction in urban and rural areas. In this study, based on panchromatic images from GeoEye-1 satellites and a site investigation of a 125 km² belt zone compositing of 5 square sampling windows (which is 5 km*5 km from window 1 to window 5) in the northern urban-rural ecotone of Beijing. Land use, composition and distribution of green space and plant species in belt zone were analyzed. Results show that:(1) the impervious surface area index(ISAI), green space, and water area accounted for 42%, 56.08%, and 1.92% respectively of total belt zone area. Furthermore, along the urban-to-rural gradient, ISAI was reduced and green space increased gradually. The pattern of green space dominated by urban green area turns to protective and productive green area such as traditional farmlands or orchards, ultimately landscape forest in mountain areas. (2) There were 480 plants species belonging to 313 genera and 98 families in the study area, in which 337 species were plants native to Beijing accounting for 70.21% of total plant species, 62 species were introduced from other regions of and 81 species were introduced from foreign countries accounting from 12.92% and 16.88% of total plant species respectively (3) The belt zone contained all 15 areal-types of the Chinese seed plant genera, among them, the North Temperate elements、Pantropical elements、Cosmopolitan elements and Old World Tropic elements accounting for 23.3%, 17.3%, 14.1%, and 10.9% respectively of total genera. Total tropical elements accounted for 31.6%, which consisted of part of the lesser species genera and the vast majority of single species genera. (4) Plant species richness distributed in the order of window 3 > window 2 > windows 1 > window 4 > window 5. The ratios of native plants increased gradually from 66.29% in window 1 to 86.93% of window 5 along the urban-to-rural gradient. The proportion of plant species introduced from foreign countries was higher than introduced species from other regions of China in all sampling windows.