The invention provides a method for growing a carbon nitride protective layer on a wood surface. By using a wood board (fir wood, pine wood or the like) as the research object and graphite-phase carbon nitride as a target, a spattering process is performed to grow a carbon nitride protective layer on the wood surface. The prepared wood, the surface of which the carbon nitride protective layer is grown, has the advantages of favorable hydrophobicity, favorable wear resistance, favorable corrosion resistance, favorable weather resistance and favorable dimensional stability, and has favorable function of purifying volatile organic compounds in air. The method is convenient and simple in technique, and has obvious economic and social benefits.