A stress estimation system which estimates stress of a user includes a walking speed acquisition unit configured to acquire walking speed information indicating walking speeds of a user in each of the morning and the afternoon at a preset place, an estimation unit configured to calculate a comparison value between the walking speeds in each of the morning and the afternoon indicated by the acquired walking speed information, and to estimate stress of the user based on the calculated comparison value, and an output unit configured to output information in accordance with the estimated stress of the user.
