The control of marine biofouling has gained significant attention because the uncontrolled adhesion of marine organisms onto synthetic surfaces leads to serious problems. Here, we demonstrate a facile method to inhibit the adhesion of marine organisms using the sulfated polysaccharide, heparin. Heparin was conjugated with an adhesive molecule, catechol, and the resulting adhesive heparin was used as a surface coating for stainless steel, a material commonly used for marine vessels. Immersion of stainless steel surfaces in a solution of adhesive heparin resulted in a stable heparin coating. The marine antifouling property of the surface was confirmed using marine diatom adhesion assays, which revealed that the adhesive heparin coating reduced diatom adhesion by ~75%, as compared with untreated surfaces.