A comparison device comprising: a processor; a display unit; and a storage unit, wherein the processor is configured to compare an imaged face image obtained by imaging a face of a comparison target person to a face image of the comparison target person, which has been registered in the storage unit, by calculating (S22, S23) partial similarity scores between the imaged face image and the registered face image in partial areas, each partial area being a component constituting a face and being one of a plurality of predetermined partial areas, the plurality of predetermined partial areas including a left-eye area, a right-eye area, a nose area, a mouth area and a forehead area, in a case where it is determined that the comparison target person as an imaged target in the imaged face image is not a subject of the registered face image, as a result of the comparison, the processor is configured - to determine whether or not a blocking object is provided in the image face image by calculating feature values of partial areas having a possibility of being hidden by the blocking object, for each blocking object, and acquiring a blocking object score, being defined for each type of blocking object, through calculation using the calculated feature value by means of a support vector machine, in which learning regarding whether or not the blocking object is provided has been performed, and - to cause the display unit to present information indicating that a blocking object is to be removed, to the comparison target person, based on a result obtained by the determining whether or not the blocking object is provided in the imaged face image and on the partial similarity score in the partial area or partial areas corresponding to the blocking object. a processor; a display unit; and a storage unit, wherein the processor is configured to compare an imaged face image obtained by imaging a face of a comparison target person to a face image of the comparison target person, which has been registered in the storage unit, by calculating (S22, S23) partial similarity scores between the imaged face image and the registered face image in partial areas, each partial area being a component constituting a face and being one of a plurality of predetermined partial areas, the plurality of predetermined partial areas including a left-eye area, a right-eye area, a nose area, a mouth area and a forehead area, in a case where it is determined that the comparison target person as an imaged target in the imaged face image is not a subject of the registered face image, as a result of the comparison, the processor is configured - to determine whether or not a blocking object is provided in the image face image by calculating feature values of partial areas having a possibility of being hidden by the blocking object, for each blocking object, and acquiring a blocking object score, being defined for each type of blocking object, through calculation using the calculated feature value by means of a support vector machine, in which learning regarding whether or not the blocking object is provided has been performed, and - to cause the display unit to present information indicating that a blocking object is to be removed, to the comparison target person, based on a result obtained by the determining whether or not the blocking object is provided in the imaged face image and on the partial similarity score in the partial area or partial areas corresponding to the blocking object. - to determine whether or not a blocking object is provided in the image face image by calculating feature values of partial areas having a possibility of being hidden by the blocking object, for each blocking object, and acquiring a blocking object score, being defined for each type of blocking object, through calculation using the calculated feature value by means of a support vector machine, in which learning regarding whether or not the blocking object is provided has been performed, and - to cause the display unit to present information indicating that a blocking object is to be removed, to the comparison target person, based on a result obtained by the determining whether or not the blocking object is provided in the imaged face image and on the partial similarity score in the partial area or partial areas corresponding to the blocking object.