Abstract: measurement device and a measurement method for measuring a temperature and an emissivity of a measured surface are provided. The measurement device includes a reflection converter, an optical receiver and a data processor. The reflection converter includes a reflector having a through hole and an absorber tube shifted between a first measurement position and a second measurement position relative to the reflector. In the first measurement position, the light incident end of the absorber tube approaches or contacts the measured surface, such that the optical receiver forms a first electrical signal. In the second measurement position, the light incident end of the absorber tube is located at or outside the through hole, such that the optical receiver forms a second electrical signal. The data processor is configured to determine a temperature and an emissivity of the measured surface according to the first electrical signal and the second electrical signal.