1. An image processing apparatus comprising: image storing means for storing image data representative of a single unit image or a plurality of unit images; writing means for writing the image data in a removable storing means; list data storing means for storing list data listing the image data stored in either one of said image storing means and said storing medium; selecting means for selecting, among the image data stored in said image storing means, image data tobe written to said storing medium; and control means for updating, when the image data selected by said selecting means are written to said storing medium, the list data stored in said list data storing means every time said writing means writes one image data, and causing, after all the image information selected have been written to said storing medium, said list data to be written to said storing medium.