A diagnosis supporting apparatus includes: an image input section that inputs an endoscopic image acquired from a living tissue, a structure detection section that detects similar circular-shaped structures from an image signal corresponding to the endoscopic image inputted to the image input section, and a network detection section that detects a predetermined network shape in the endoscopic image, based on a number of similar circular-shaped structures detected by the structure detection section, areas of the similar circular-shaped structures, distances between the respective similar circular-shaped structures, or a number of connections between the respective similar circular-shaped structures.