The invention relates to the technical field of information security. The invention particularly relates to a financial information outsourcing management system based on a block chain. The system comprises a file management subsystem. The file management subsystem comprises a file processing module and a file uploading module. The file processing module is used for obtaining a stored file and dividing the evidence storage file into a plurality of data blocks. The file uploading module is used for uploading all the data blocks to the block chain; wherein the file processing module presets a file threshold value. When the stored file is greater than the file threshold value, the file processing module is used for generating a unique file identifier according to the stored file, the file uploading module is used for uploading the file identifier to the block chain, and the user node is used for acquiring the stored file according to the file identifier. By adopting the scheme, the condition of network congestion caused when large files are transmitted on the block chain can be reduced.