An exemplary uncomfortable sound pressure estimation system includes: a sound stimulation scheduling section configured to determine points in time of outputting a group of sound stimulations so that times of measurement for event-related potentials in response to the second sound and third sound arrive after a predetermined noise-lingering time has elapsed since a next point of occurrence of periodic noise an event-related potential characteristic amount extraction section configured to receive the points in time of outputting the sound stimulation group, and extract a characteristic amount of an event-related potential of the electroencephalogram signal based on each point of outputting the group of sound stimulations as a starting point and an uncomfortable sound pressure determination section configured to determine an uncomfortable sound pressure for the frequency of the sound stimulation group.