A high‐precision thermometer system has been developed using a carbon resistor (Allen‐Bradley type) as the sensing element. The resistor is in the frequency determining circuit of a stabilized Wien bridge oscillator. Thus temperature changes are displayed as frequency shifts. The frequency is read directly from a Hewlett‐Packard type 523B counter. When operated in the neighborhood of 100 kc at 4.2°K the sensitivity is approximately 50 kc/deg. This corresponds to a temperature resolution of 20 &mgr;deg, when used with the above counter. Resolution can be improved by observing higher harmonics. The power input to the resistor is of the order of 10−2&mgr;w. The time for a temperature measurement is 1 sec, and response times to changes are limited only by equilibrium in the thermometer. Absolute accuracy is essentially limited only by the determination of the helium vapor pressure during calibration.