For automatically transmitting an image file, a system transmits the file automatically through specifically specifying information for file transmission such as an address of a destination. The system includes a memory for storing a data file and an automatic transmission control file for briefly describing information of a file name of the file to be transmitted and a destination address, and a communication unit for transmitting the data file according to the automatic transmission control file. Therefore, the system can transmit the data file automatically only by having a memory storing the data file and automatic transmission control file connected to the communication unit.