An endoscope system of the present invention includes an image pickup section that picks up an image of an object, a position detection section that detects a position indicating a predetermined object in the image of the object obtained by the image pickup section and a probability calculation section that calculates a probability value as a degree indicating accuracy of the position being the predetermined object using first information obtained from the image and second information on a condition of the object whose image is picked up by the image pickup section.
