Most of the plants and trees are landscaping plants at the university campus, Thus, the natural flora can be found on sidewalks like urban area. In order to investigate the flora on sidewalks of the university campus, the vegetation survey was done. The study site is Natural Science Campus, Sungkyunkwan University which is located at Suwon, Korea. Vascular plants surveyed were consisted of 130 taxa, 39 families, 99 genera, 115 species, 15 varieties. Indigenous weeds was 101 species (77.7%). Naturalized weeds was 29 species (22.3%). In the families, Compositae 30 species (23%), Gramineae 18 species (14%), Leguminosae 9 species (7%), Caryophyllaceae 8 species (6%), Cruciferae 8 species (6%), Polygonaceae 5 species (4%), Euphorbiaceae 5 species (4%), Scrophulariaceae 4 species (3%), Rosaceae 3 species (2%), Violaceae 3 species (2%), Convolvulaceae 3 species (2%) and etc. 34 species (27%). Life Form of flora in the site by Raunkiaer classification was Therophytes 67 species (51.5%), Hemicryptophytes 46 species (35.4%), Geophytes 8 species (6.2%), Nanophanerophytes 4 species (3.1%), Phanerohytes 3 species (2.3%) and Chamaephytes 2 species (1.5%). Naturalized Ratios was 10.7%.