To provide a digital image radio transmitter for quick process with less delay time, and to provide its image data processing method.

The digital image radio transmitter compresses image data of a photographed image for digital radio transmission, wherein the digital image radio transmitter comprises: a temporary memory part which has a memory capacity being smaller than the capacity corresponding to a single frame of the image data of photographed image and sequentially and temporarily stores the image data of photographed image in units of minimum unit regions that constitute a portion of the signal frame and can be separately compressed; an image compression process part which sequentially compresses the image data read in units of minimum unit regions from the temporary memory part; a transmission buffer which accumulates the image data that the image compression process part compresses; and a transmission part which sequentially transmits the image data read from the transmission buffer at a fixed transmission rate.