The purpose of this work was to study the different mechanisms of coloring of structural color and the color rendering characteristics of the reflection or transmitted light of the grating microstructure. Using FDTD Solutions and Matlab as the platform, FDTD (finite difference time domain method) theory was employed to establish a two-cycle the simulation model of the grating structure: symmetrical and asymmetrical structure model bionic structure model to study the structure of color theory using color theory. The reflection grating spectral characteristics of the two curves and color differences were obtained. In conclusion, periodic grating microstructures could create spectral color, apparent deviation occurred at the peak position of the change of the structural model parameters, the color of light changed from asymmetric bionic structure model blue light (spectral wave peak at 455 nm) to symmetric bionic structure model green light (spectral wave peak at 550 nm), providing more theoretical basis for the manufacture of artificial structures with controllable color characteristic color and coloration law of grating structural color.