The invention discloses a file transferring method with self-
adaptive control of transmission speed and a
system thereof; UDP protocol is adopted to transfer file data, other commands are carried outby TCP protocol; the file data takes 'block' as a basic unit for each transferring and verifying the completeness, and transmission speed is adjusted by adopting a way of dynamically adjusting the size fine grit of a transmission 'block'; the file is divided into 1-N file fragments by a
server, and each file fragment is transmitted by a UDP send data; the
server transmits according to the size ofthe presetting block, a
client side verifies the result weather to be retransmitted by requesting the
server according to the completeness of the received block, if the sever receives the retransmitting request from the
client side, the size of the block can be dynamically adjusted. In addition, the transmission speed is adjusted by dynamically adjusting the number of transmission threads. In theinvention, less network expense is increased, and network resource accessed by the
client side can be effectively utilized, and the transferring time of the whole file is reduced.