In an electronic endoscope system, an individual channel of a frequency band is allocated to each of a plurality of electronic endoscopes. When a release switch of the electronic endoscope is operated to record an endoscopic image, a picture signal of the endoscopic image is modulated into a radio frequency signal, and a header representative of the allocated channel is attached to the radio frequency signal, before sending it as an electric wave to a storage server through the allocated channel. The storage server is provided with a plurality of data storages for the individual channels. In the storage server, the received radio frequency signal is demodulated into the original picture signal, and an I/O port sorts the picture signal according to the attached header, to write it as the endoscopic image in the data storage corresponding to the channel represented by the attached header.