An information processing device includes: a heart rate acquiring unit configured to acquire a heart rate of a subject； a feature extracting unit configured to extract a feature of a heart rate in relation to intake of alcohol, from a temporal change in the heart rate acquired by the heart rate acquiring unit； a storage unit configured to store beforehand information about a temporal change in the heart rate in relation to intake of alcohol； and a determining unit configured to determine whether the temporal change in the heart rate acquired by the heart rate acquiring unit is due to intake of alcohol, in accordance with the feature extracted by the feature extracting unit and the information stored in the storage unit.
