Objective: To study the distribution characteristics of microorganisms on the surface of pericarpium citri reticulatae(PCR) stored in standard warehouses in different years. Method: High-throughput sequencing method was used to sequence the sequence data of the PCR with the storage time of 0， 1， 2， 3， 4， 5， 10， 15 and 30 years. The distribution characteristics of fungi and bacteria on the surface of PCR were analyzed by OUT analysis， alpha diversity analysis and principal component analysis. Conclusion: The species richness of the nine samples with different storage time increased first and then decreased. When the storage time was 2， 3， 4， 5 and 10 years， the number of species was more and the homogeneity was better. The dominant bacteria in the first 10 years were mainly Penicillium and Aspergillus. Different from fungi， the change trend of the number of bacteria species fluctuates greatly， but the change range is small. The dominant bacteria were Sphingomonas， Lactobacillus， Cladosporium and Panthia. They are the dominant bacteria with 0， 1， 2 and 4 years storage time respectively， and Rumen cocci with high relative abundance in each year. Discussion: A model was established to judge the storage time of PCR according to the distribution characteristics of fungi in different years.