The present invention aims at permitting numerous user terminals to share protocols as common resources. A vendor terminal or user terminal registers a pair of a protocol and a medical image, which is produced during scanning performed according to the protocol, by recording data in a protocol/medical image database included in a protocol management server. The user terminal acquires a medical image from the protocol management server over a network, and displays it on a display device. Moreover, the user terminal downloads a required protocol from the protocol management server and sets it in a medical diagnostic imaging system.