To develop a cationic UV curable, tough fouling-release coating for marine vessels, a difunctional oxetane monomer was used to copolymerize with the epoxy-siloxane oligomer at loading levels from 10% to 40% wt.. The resulting coatings showed enhanced solvent resistance, impact resistance and modulus, while remained hydrophobic before and after immersion in artificial sea water. In marine microorganism bioassay, these oxetane toughened coatings showed no leachate toxicity and the coating surfaces were non-toxic to biofilm growth. The fouling removal performance for these coatings was found to be microorganism dependent. Live barnacle reattachment assay showed that the toughened coatings had a removal force comparable to the reference silicone coatings Dow Corning T2 and 3140.