Medical sponges are widely used in wound management, however the adhesion of bacterial or wound tissue to them may cause infection or secondary damage to patients. In this work, anti-bioadhesive polyvinyl alcohol-formaldehyde sponges with zwitterionic coating were prepared by the dip-coating process using the reactive zwitterionic phosphorylcholineated polyvinylamine (PVAm-PC) and commercial silane coupling agent KH560 at different mass ratios, and their structure, physicochemical, biocompatible and anti-bioadhesive properties were investigated. As compared to pristine sponges, the PVAm-PC-KH560 (PPK) modified sponges with the interconnected pore structure had almost unchanged water vapor transmission rate but decreased swelling degree to a certain extent possibly due to the formation of rigid Si–O–Si networks in the sponges. In vitro biological evaluation confirmed that PVAm-PC-KH560 modified sponges were not cytotoxic and had good resistance to bacteria adhesion with only ∼16% and ∼11% relative bacterial adhesion rate for E. coli and S. aureus respectively. And the optimized PPK-2 sponge showed the best comprehensive bacterial adhesion inhibition properties. Further adhesion assay of L929 fibroblasts showed that PPK-2 sponge could significantly reduce the adhesion of L929 fibroblasts. The results strongly suggested that dip-coating with zwitterionic PVAm-PC and KH560 may provide a promising and facile method to construct an anti-bioadhesive surface for biomedical applications.