First ratio acquisition means of a display timing determination device acquires, for each voice, a first ratio that relates to intervals between output timings of voices. Second ratio acquisition means acquires, for each piece of character information, a second ratio that relates to intervals between provisional display timings of pieces of character information. Identification means identifies, based on the first ratio of each voice and the second ratio of each piece of character information, an association relationship between the voice and the piece of character information. Display timing determination means determines a definitive display timing of each piece of character information based on the association relationship.