The temperature increase of thermally insulated skin provides useful information about its blood flow and the blood temperature. The measurement of skin temperature by a contact thermometer, such as a thermistor, is not accurate, because it depends on the pressure exerted on the skin by the thermometer. In order to have reproducible measurement of the skin temperature, noncontact temperature measurement is preferable. Suitable insulation is achieved by using a cylinder of lowthermal-conductivity material, covered by polyethylene layers, which is applied on the skin. The polyethylene layers permit partial transmission of the infrared radiation through it. Preliminary results show that both the transient and the steady-state temperature increase can be obtained from measurements of radiation transmitted through the thermal insulation that was applied to the skin, and that the steady-state temperature increase is more closely related to tissue blood flow than the uncovered-skin temperature is.