The article presents nineteen ruderal plant communities based on two hundred and twenty-five relevés on the border of Praeillyricum and Noricum floristical region in Southwest Transdanubia in Hungary.The following associations were determined: Hordeetum murini, Polygono arenastri-Lepidietum ruderalis, Malvetum neglectae, Onopordetum acanthii subass. typicum, Onopordetum acanthii subass. arctietosum, Carduo-Onopordetum acanthii, Convolvulo-Agropyretum repentis, Lepidietum drabae, Balloto-Malvetum sylvestris, Arctietum lappae, Carduetum acanthoidis, Arctio-Artemisietum vulgaris, Conietum maculati, Cannabietum spontaneae, Tanaceto-Artemisietum vulgaris subass. typicum, Dauco-Picridetum , DC Calamagrostis epigeios [Onopordetalia], Sambucetum ebuli, Chaerophylletum bulbosi. Anthriscetum sylvestris , one of the most important hilly associations, as well as Dauco-Picridetum , DC Calamagrostis epigeios [Onopordetalia] and Onopordetum acanthii subass. arctietosum were described at the first time in Hungary.Moreover, soil analysis of ruderal communities was performed. Based on the analyses of ruderal soils, the soils were neutral in chemical reaction, regarding to the texture were mainly loam, while clay and sand had smaller shares.