The invention discloses a preparation method of surface plasmonic crystal and comprises the following steps: arraying submicron or micron silica microspheres on a substrate to obtain a colloidal crystal of two-dimensional hexagonal close-piled microsphere array; utilizing the colloidal crystal as a template, depositing nano metal grains on the surface of the microspheres until a metal semispherical shell membrane is formed on the surface of the microspheres of the colloidal crystal template, and bonding metal leads on the surface of the metal semispherical shell membrane; filling organic polymer into the void of the crystal template until coating the entire template and the contact points of the metal leads and the metal semispherical shell membrane; removing silica colloidal crystal template and the liner so that an organic polymer porous membrane is formed; depositing metal in the spherical cavity of the organic polymer porous membrane by taking the organic polymer porous membrane as the cathode; solving and removing the organic polymer by using methylbenzene to obtain the surface plasmonic crystal which is controllable in terms of shape and appearance. The inventive method features simple technique, and can perform precise control on the shape and appearance of the metal grains.