An audio processing apparatus includes an audio signal acquisition unit which acquires an audio signal of a musical piece, a feature value extraction unit which extracts a predetermined type of feature value from the audio signal acquired by the audio signal acquisition unit in time series, a change point detection unit which detects a change point in which the amount of change of the feature value extracted in time series by the feature value extraction unit is changed to be greater than a predetermined threshold value, a hook analysis unit which analyzes a hook place of the audio signal based on the feature value extracted by the feature value extraction unit in block units with the change point detected by the change point detection unit as a boundary, and a hook information output unit which outputs the hook place analyzed by the hook analysis unit as hook information.