For measuring the heat flux on a cylindrical or plane wall, a heat flux sensor was especially designed for surfaces with small dimensions (5 cm × 5 cm). Chromel-constantan thermocouples with a diameter of 50 μm and a teledeltos paper were used to make a prototype. This sensor is based on compensation measuring methods so it needs no calibration. Two experimentals results obtained are comparable to within 8% and 5% to those obtained by the direct method. Using microelectronic technology, the experimental sensor was investigated further to identify possible fields of application, and to reduce its size.