The zwitteronic copolymer P(MPC-co-DMA) (PMPCD) was synthesized based on the free radical copolymerization using dopamine methacrylamide (DMA) and 2-methacryloyloxyethyl phosphorylcholine (MPC) as monomers. The PMPCD was grafted onto substrate surface with dopamine (DA) as the anchor, forming an antifouling coating. Furthermore, silver ions were reduced to silver nanoparticles (AgNPs) by polydopamine (PDA) in situ, achieving the preparation of a dual-functional PDA/PMPCD-AgNPs coating with antifouling and antibacterial properties. The PDA/PMPCD-AgNPs coating was characterized by SEM and XPS, confirming the successful preparation of the coating. According to the results obtained from water contact angle measurements, antibacterial assays and biocompatibility experiments. the introduction of PDA/PMPCD-AgNPs coating significantly enhanced the hydrophilicity, antibacterial efficacy and biocompatibility of the substrate surface. Specifically, the antibacterial rates against Escherichia coli and Staphylococcus aureus were both above 97%, the anti-protein adsorption rate reached 94%. Moreover, it could reduce platelet adsorption and inhibit platelet activation while demonstrating low hemolysis rates and excellent cell viability. Therefore, this dual-functional anti-fouling and antibacterial coating holds wide application prospects in the field of biomaterials.