The invention discloses a large data classification system. The large data classification system is formed by sequentially connecting a data source, a data classification unit, a data numbering unit and a cloud database, wherein the data numbering unit further comprises data position numbering, data time numbering and data capacity numbering, the data classification unit effectively classifies data of the data source, the data numbering unit is used for classifying data positions, data time and data capacity of the same-type data in different classifications, the classifications are stored in the cloud database, classified storage of a tree-shaped classification structure is achieved, the data needing to be processed are greatly reduced, the data can be classified rapidly and accurately in a short time, and therefore the executing efficiency of a data classification process is effectively improved, complexity of related data management is reduced, and computation load of the system is also relieved.