The presented study describes a method for the preparation and modification of cylindrical polyurethane structures with polyvinylpyrrolidone (PVP) hydrogel coating. The modified polyurethane scaffolds were fabricated using the phase-inversion technique and intended to be used as a vascular prosthesis. The proposed modification method involves a two-step Fenton-type reaction. Physicochemical analysis (Fourier transform infrared spectroscopy, scanning electron microscopy) confirmed the presence of the hydrogel coating. The influence of PVP and polymerization initiator (cumene hydroperoxide) concentrations on hydrogel’s properties were examined. The higher concentrations of reagent were used, the thicker coating was obtained. After modification, the material’s surface becomes more hydrophilic in comparison to pristine polyurethane. Cytotoxicity assay (MTT test) confirmed that PVP-coating is not toxic. The introduction of hydrogel coating resulted in a significant decrease in the fibrinogen adsorbed to the material’s surface as compared to a non-modified polymer. Platelet adhesion assay demonstrated almost no platelet adhesion to the modified surfaces.