The image data transmission apparatus for transmitting image data signal to a plurality of end devices corresponding to the request from each end device, divides the input image data signal into a plurality of unit image data to subsequently store it on the recording medium, controls operation of the plural storing means so that the unit image data for each end device is read out by time division from the recording region in each storing means which is different from each other corresponding to requests from each end device, combines the unit image data for each end device which is read out from each storing means by each end device to form image data signal for each end device, and transmits it to each correspond end device.