A similarity analyzing device includes: an image acquisition section which acquires picked-up images with which image pick-up dates and/or times are associated; and an image registration section which registers a face image showing a picked-up face and with which an image pick-up date and/or time is associated. The device further includes: a degree of similarity calculation section which detects a face in each of picked-up images acquired by the image acquisition section and calculates the degree of similarity between the detected face and the face in the face image registered in the image registration section; and a degree of similarity reduction section in which the larger the difference between the image pick-up date and/or time associated with the picked-up image and that associated with the face image is, the more the degree of similarity of the face calculated by the degree of similarity calculation section is reduced.