The forward characteristics of a cryogenic GaAlAs temperature sensor diode (Lake Shore Cryotronics, Inc.) have been presented in the temperature range 10–300 K and for fixed current values between 10 nA and 500 μA. The upturn in the forward characteristic below 35 K was found to shift to lower temperatures by reducing the current. The sensitivity at low temperature was found to reduce with current (I) according to a power law. The sensitivity at high temperature was found to increase linearly with decrease in lg (I).