An endoscope observation assistance apparatus includes an image information acquiring part to acquire and display a captured image of a luminal organ captured by the endoscope device on a display, a lesion information acquisition part to detect a predetermined lesion based on the captured image and to acquire lesion information regarding the lesion, a lesion disappearance determination part to track the lesion based on the captured image and the lesion information and to determine whether or not the lesion has disappeared from the captured image, and a notification part to notify a determination result when the lesion disappearance determination part determines that the lesion has disappeared from the captured image. Alternatively, the notification part may notify a lesion detection when a short time period passes after the lesion detection by the lesion information acquisition part.