To provide an institution retrieval device with which a user can easily retrieve an institution without the restriction of an utterance order, and to provide its method.

A regional name and the classification name of the institution inputted in an arbitrary procedure are recognized as narrowing-down conditions, by simultaneously referring to all genres name dictionary and a regional name dictionary as narrowing-down dictionaries, and thereby, the number of institution names which satisfy the narrowing-down conditions is acquired. An institution name dictionary is prepared when the number of institution names is the prescribed number of institutions or less, and the voice recognition processing of the institution name to be inputted by voice is performed by using the prepared institution name dictionary.