A bruxism detection device includes: a sound collection unit that collects a sound produced from a subject and outputs a sound signal corresponding to the collected sound a bruxism candidate detection unit that detects a period of a sound having a feature that is characteristic of bruxism, from the sound signal, as a bruxism candidate period a breath detection unit that detects a period of a sound having a feature corresponding to a predetermined breathing state, from the sound signal, as a specific breathing period and a determining unit that determines that the subject has bruxed, when the specific breathing period is present before or after the bruxism candidate period.
