The invention provides application of a polymer composite board as a mobile vessel wave cutter, which is characterized in that the polymer composite board is used as the mobile vessel wave cutter. The polymer composite board is compounded by a modified phenol-formaldehyde resin sizing material added with carbon fiber and an alkali-free glass fiber fabric. The application has the advantages that the polymer composite board has light deadweight, and is only one third of a steel plate, thereby greatly reducing the deadweight of a mobile vessel, and reducing the transportation cost of a chemical liquid. Meanwhile, the polymer composite board has the advantages of good corrosion resistance, fatigue resistance and high specific strength, and has strength superior to vessel steel, thereby enlarging the range of transporting a liquid chemical medium. Repeated experiments prove that: the polymer composite board has excellent wave cutting performance, and can be completely used as the mobile vessel wave cutter.