Peacock feather is one of the typical cases with structural colors. In the present article, we found that flamboyant colors in the “eye spot” of male peacock came from photonic crystal structure by observing the surface texture with SEM and reflectance spectrum with fiber spectrometer, and different color regions correspond to various structure cycles and surface appearances of the microstructure. The reflectance spectrum showed that the location of reflective peak shifted with the changes in the incident angles. The theory that the color is caused by microstructure was verified by the phenomenon that reflective peak exhibited red-shift with the time-varying after soaking in isopropyl alcohol. This study paves the way for fabricating functional composite materials with peacock feather-like photonic crystal structure.