The invention discloses a file transmission method and system based on power distribution automation, and the method and system are used for achieving the purposes that a first receiving and transmitting region copies a to-be-transmitted file to an isolation region, and transmits the received to-be-transmitted file to a second receiving and transmitting region through the isolation region and a communication protocol. After the to-be-sent file is received in the second receiving and transmitting region, the second receiving and sending area sends a receiving receipt to the first receiving andsending area through the isolation area, and after receiving the receiving receipt sent by the isolation area, the first receiving and sending area confirms that file transmission is completed and ends the operation. The invention has the advantages that the problem of loss of forward and reverse isolation transmission files is effectively solved, meanwhile, the transmission result is fed back intime, effective and timely information is provided for operators, and normal operation of a power system is facilitated.