Zwitterionic thin films containing α-amino phosphonic acid moieties were successfully introduced on silicon surfaces and their antifouling properties were investigated. Initially, the substrates were modified with a hybrid polymer, composed of poly(methylsilsesquioxane) (PMSSQ) and poly(4-vinyl benzaldehyde) (PStCHO). Next, a Kabachnik-Fields post-polymerization modification (sur-KF-PMR) of the functionalized aldehyde surfaces was conducted with different amines and dialkyl phosphonates. After subsequent deprotection reaction of dialkyl phosphonates, the obtained zwitterionic surfaces were characterized by various techniques and we found excellent antifouling properties of the resulting films. Zwitterionic α-aminophosphonic acid surfaces are prepared by successful surface-Kabachnik-Fields reaction of an aldehyde-functionalized surface with amines and dialkyl phosphonates and subsequent deprotection. The obtained zwitterionic surfaces exhibit antifouling properties.