Multi-wavelength photochromic storage is a new optical storage method with high storage capacity based on photochromic principle. The storage mechanism, the system structure and disc structure of multi-wavelength photochromic storage are presented. Three-wavelength photochromic storage experiment on a three-wavelength photochromic storage system is carried out. The results show that three materials used in the experiment can be used in multi-wavelength photochromic storage and the contrast of the readout signal is high and little crosstalk is generated. The contrast of the readout signal remains high after low-speed reading out 50 times.