A stress measurement device includes a first obtaining unit obtaining thermal data including information indicating a temperature of a measuring region, a second obtaining unit obtaining data related to stress occurring in one part of the measuring region, and a controller finding stress occurring in the measuring region from the thermal data and the data related to the stress. The controller finds, first waveform data respectively on the one part and a part other than the one part based on a change with time of the thermal data, and second waveform data based on a change with time of the data related to the stress. The controller finds, disturbance data through a deduction of the second waveform data from the first waveform data on the one part, and stress data indicating stress occurring in the part through a deduction the disturbance data from the first waveform data on the part.