The power supply possessing a low temp. drift and consisting of semiconducting elements includes two p-n junction located in a single temp. field and possessing different widths of the forbidden bands, or two schottky diodes possessing different potential heights. Their forward currents must be regulated until the same dependence of their forward voltage drift upon temp. is obtd.. The output voltage of the supply is the difference between their forward voltages and is equal to the difference between widths of their forbidden bands or potential heights at the zero degree of the absolute scale of temp.. It can be used in the temp. range of 4.2K-800K without any noise resulting from the backward breakdown of the p-n junction. A reference power supply having performances of a low inner resistance and a low drift with temp. can be realized when using a direct current power supply.