An action analysis device includes: an acoustic analysis unit 1 for analyzing input acoustic information, and generating acoustic analysis information indicating a feature of the acoustic information; a time difference determination unit 2 for determining a time difference between when an acoustic event identified by the acoustic analysis information occurs and when an event corresponding to the acoustic event occurs in input video obtained by capturing an image of a crowd; and an action analysis unit 3 for analyzing an action of the crowd corresponding to the acoustic event, using the input video, the acoustic analysis information, and the time difference.