There is provided a stress management system that manages psychological stress of a user. The system includes: a first sensor that detects biological data of a user; a second sensor that detects life log data indicating an activity history of the user; a generator that generates stress data using the biological data, the stress data indicating a time series variation in a stress level of the user; an estimator that, when the stress level included in the stress data exceeds a threshold value, estimates whether or not stress experienced by the user is interpersonal stress that is caused by contact with other people, using the life log data; and a notifier that notifies the user of a result of the estimation by the estimator.