Sulfated polysaccharides inhibit the infection of viruses such as HIV, influenza, and dengue fever viruses by electrostatic interaction between negatively charged sulfate groups of sulfated polysaccharides and positively charged amino acids of virus surface proteins. This review deals with recent results on the development of membrane 〓lters with virus adsorption functionality and their mechanism by using surface plasmon resonance (SPR) and dynamic light scattering (DLS).