A circuit for temperature compensation is connected to a sensor. The circuit includes an impedance element and a voltage controller. The impedance element has one terminal connected to a second terminal of the sensor, and the other terminal connected to a low voltage source. The voltage controller has an input terminal connected to the second terminal of the sensor to receive a to-be-measured voltage, a reference terminal receiving a reference voltage, and an output terminal is connected to the first terminal of the sensor to adjust a voltage level of the high voltage source. When the sensor output voltage varies due to change of an environment temperature, the voltage controller compares the reference voltage with the varied to-be-measured voltage to adjust the voltage level of the high voltage source, thereby restoring the varied sensor output voltage to a voltage level before being varied.