An image processing apparatus that is capable of restoring a degraded image with high accuracy The image processing apparatus acquires image data including an image of character information and identifies a character type of the character information. A learned model adapted to the identified character type is acquired from a plurality of learned models subjected to machine learning using images for learning, which are associated with a plurality of character type conditions, respectively, and correct answer images associated therewith. The image of character information is input to the acquired learned model to restore the image of character information.