For identification of individual electronic cassettes, a different label is attached to each of the electronic cassettes. Selection buttons for selecting one of the electronic cassettes are provided on a console in correspondence with the respective electronic cassettes. A cassette ID is assigned to each of the electronic cassettes, and the console communicates with the selected electronic cassette using the cassette ID assigned to the selected electronic cassette. Data of correspondence between the cassette ID and the label is memorized for each electronic cassette. The same label is displayed on the selection button as the label on the corresponding electronic cassette, allowing confirming whether the electronic cassette actually positioned for imaging coincides with the electronic cassette selected on the console.