Disclosed are a speech retrieval apparatus and a speech retrieval method for searching, in an audio file database, for one or more target audio files by using one or more input search terms. The speech retrieval apparatus comprises a related document obtaining unit configured to search, in a related document database where documents related to audio files in the audio file database are stored, for one or more related documents by using the search terms; a correspondence audio file obtaining unit configured to search, in the audio file database, for one or more correspondence audio files corresponding to the obtained related documents; and a speech-to-speech search unit configured to search, in the audio file database, for the target audio files by using the obtained correspondence audio files.