An object of the present invention is to provide an image diagnosis assistance apparatus, an endoscope system, and an image diagnosis assistance method that are capable of appropriately performing reporting by using screen display and audio. An image diagnosis assistance apparatus according to a first aspect of the present invention includes an image acquiring unit that acquires a chronological medical image, a recognizing unit that performs recognition of a region of interest in the acquired medical image, a reporting unit that performs reporting of a result of the recognition by using screen display and audio, and a determining unit that makes a determination on an examination status. The reporting unit performs reporting by using the screen display regardless of a result of the determination, and performs reporting by using the audio in either of a first mode of using audio having a first reporting level and a second mode of using audio having a second reporting level lower than the first reporting level, in accordance with a result of the determination.