A similar case history search device comprises: a weighting determination unit (170) which determines, on the basis of inter-item relation information which has predetermined an association between each image feature value which is extracted from a medical image and either each X-ray interpretation item or each condition name which is included in an X-ray interpretation report for the medical image, a weighting for each of a plurality of image feature values which are extracted from an X-ray interpretation subject image which increases the greater the association between the image feature value and either the X-ray interpretation item or the condition name which is included in the X-ray interpretation subject report； and a similar case history search unit (180) which, by weighting, with the weighting for each image feature value which is determined with the weighting determination unit (170), the plurality of image feature values which are extracted from the X-ray interpretation subject image and the plurality of image feature values which are extracted from a medical image which is included in case history data which is entered in a case history database, and comparing said feature values, searches for case history data which includes a medical image which is similar to the X-ray interpretation subject image.La présente invention concerne un dispositif de recherche d'antécédents médicaux similaires, qui comprend : une unité de détermination de pondération (170) qui détermine, sur la base d'informations de relation inter-items ayant permis la prédétermination d'une association entre chaque valeur de caractéristique d'image qui est extraite d'une image médicale et soit chaque item d'interprétation radiologique soit chaque nom de pathologie qui est inclus dans un rapport d'interprétation radiologique de l'image médicale, une pondération pour chaque valeur de caractéristique d'image parmi une pluralité de valeurs de caractéristiques d'image qui sont extraites d'une ima
