Polyelectrolyte multilayers (PEMs) consisting of hyaluronic acid (HA) and chitosan (Ch) are extensively studied for biomedical applications and suppress bacterial and protein attachment. Here, we prepared and tested HA/Ch PEMs as marine fouling-release coatings. PEMs were constructed by layer-by-layer assembly using spin coating. The multilayers were crosslinked for enhanced stability in the sea water environment by chemical and thermal treatment. Protein-repelling properties of the crosslinked multilayers were investigated by surface plasmon resonance spectroscopy. The marine antifouling and fouling-release properties were tested against the settlement of zoospores of the green alga Ulva linza and the subsequent development and removal of sporelings. With spin coating and thermal crosslinking, a thick yet homogeneous coating was obtained with antifouling properties against marine algal zoospores indicating the potential of these compounds for application in protective coatings.