This pain measurement device ( 10 ) for measuring pain experienced by a subject ( 99 ) is provided with a determination unit ( 12 ) for determining a reference stimulation intensity corresponding to reference pain of the subject ( 99 ), on the basis of a relationship between pain levels reported by the subject ( 99 ) and stimulation intensities applied to the subject ( 99 ), and a measurement unit ( 13 ) which compares electroencephalographic data measured from the subject ( 99 ) and reference electroencephalographic data corresponding to the reference stimulation intensity to measure pain experienced by the subject ( 99 ) when the electroencephalographic data is measured.