Abstract: The invention relates to a temperature control method and to a temperature control circuit. In a measured value detecting member (2) a measuring voltage (U.sub.TH) is generated which is representative of the actual temperature. In an adjustment member (1), a desired voltage (U.sub.S) is generated which is representative of the desired temperature. A difference former (inverse adder 5) determines from the measuring voltage (U.sub.TH) and the desired voltage (U.sub.S) a deviation voltage (U.sub.D) which corresponds to the deviation between the desired temperature and the actual temperature. The heating power of the heating element (14) of the temperature control circuit is regulated proportionately in dependence on the deviation voltage (U.sub.D) by shifting the phase angle (.phi.). During each line half-wave (27), the deviation voltage (U.sub.D) is compared in a comparator (comparator 11) with the descending edge voltage of a line-synchronous delta voltage (U.sub.DS).