The present invention relates to a medical image compression system and method suitable for visually lossless compression and, more specifically, to a medical image compression system and method capable of obtaining medical images at a high enough compression ratio while preventing loss in information needed to diagnose. The medical image compression system according to one example of the present invention comprises: a storage unit for storing initial learning data and an equation regarding an optimal compression ratio to compress a medical image to be diagnosed at an optimal ratio； a processor for obtaining an optimal compression ratio of the medical image to be diagnosed by using the stored initial learning data and the equation for the optimal compression ratio； and for compressing the medical image to be diagnosed at the optimal compression ratio obtained by the computation unit.
