Disclosed is an information estimation device for estimating an appropriate issue time from a time representation described in a document without intervention of any operator; wherein an information estimation device (1) which is a device for estimating an issue time of a document to be estimated, includes a candidate generation unit (11) which extracts a time representation described in the document, and on the basis of the extracted time representation, generates a plurality of possible issue time candidates having possibilities corresponding to the issue time of the document; and an issue time estimation unit (12) for obtaining a temporal proximity, for each of the plurality of issue time candidates, between the issue time candidate and other issue time candidates, and on the basis of the obtained temporal proximity, estimating the issue time of the document.