According to one embodiment, an image processing system includes a stereoscopic display device and an image processing apparatus. The stereoscopic display device is configured to enable a stereoscopic image constituted by using a predetermined parallax number of parallax images to be stereoscopically viewed. The image processing apparatus comprises a rendering processor configured to apply rendering processing to volume data serving as three-dimensional medical image data, a rendering processing controller configured to control the rendering processor so as to generate from the volume data a parallax image group composed of the predetermined parallax number or more of parallax images, and a storage controller configured to store in a memory the parallax image group generated by the rendering processor. The stereoscopic display device is configured to display the stereoscopic image constituted by selecting the predetermined parallax number of parallax images out of the parallax image group stored in the memory.
