To provide an image processor capable of retrieving a medical image by utilizing a comment described by an annotation function.

The image processor is provided with a memory 3 for relationally storing a medical image and a comment described in the medical image by the annotation function, retrieving means 4, 5 for retrieving the medical image from the memory 3 by using the comment as a key and a display means 6 for displaying the retrieved medical image and the comment together. Since a past medical image is extracted and displayed on a monitor and its comparing diagnosis can be executed, diagnostic accuracy can be improved.