Disclosed are a speech retrieval apparatus and a speech retrieval method for searching, in a speech database, for an audio file matching an input search term by using an acoustic model serialization code, a phonemic code, a sub-word unit, and a speech recognition result of speech. The speech retrieval apparatus comprises a first conversion device, a first division device, a first speech retrieval unit creation device, a second conversion device, a second division device, a second speech retrieval unit creation device, and a matching device. The speech retrieval method comprises a first conversion step, a first division step, a first speech retrieval unit creation step, a second conversion step, a second division step, a second speech retrieval unit creation step, and a matching step.