The invention provides a synthetic method of a zinc oxide nanometer nail. The synthetic method includes the following steps: (1) mixing graphite and zinc oxide powder evenly with the approximate mass ratio as 2:3; (2) sputtering a layer of a gold film on a monocrystalline silicon piece through an ion sputtering method; (3) placing the monocrystalline silicon piece with the sputtered gold film near mixed powder of the graphite and the zinc oxide powder; (4) vacuumizing the whole system, and then leading a small amount of nitrogen into the system; and (5) rising the temperature of the system to 900 to 1100 DEG C, keeping the temperature for a period of time and cooling. The synthetic method has the advantages that a zinc oxide nanometer crystal top cover is hexagonal, and the zinc oxide nanometer crystal is large in area and easy in adhesion operation. The lower portion of the zinc oxide nanometer crystal is in a shape of a thin strip and is easy to line up neatly. Simultaneously zinc oxide has good optical properties so that the zinc oxide nanometer nail becomes a nanometer material suitable for being used as a nanometer optical resonant cavity.