Distributed large file fast downloading method and system

The invention discloses a distributed large file fast downloading method and system. The system comprises a main node device, a registration center, a storage device and a distributed downloading device, and the main node device further comprises a large file analysis module, a downloading task distribution module, a downloading progress monitoring module and a file merging module; the distributed downloading device comprises a downloading task monitoring module and a downloading module; the large file analysis module is used for analyzing the size of a large file, performing logic fragmentation calculation according to the number and bandwidth of downloading devices, and transmitting a calculation result to the downloading task distribution module for processing; the downloading task distribution module is used for issuing the tasks to the registration center in sequence; the downloading progress monitoring module is used for monitoring all downloading task conditions of the large file; and the registration