There are provided a circuit and a method for regulating a gate voltage, and a sensor applying the circuit. In the circuit, an input end of the storage module is connected to a first end of a signal storage unit, an output end thereof is connected to an input end of the comparison module, an output end of the comparison module is connected to an input end of the voltage regulation module, and an output end of the voltage regulation module is connected to a transmission gate. The storage module stores electrical signals outputted by the signal storage unit. The comparison module compares at least two of the electrical signals correspond to different gate voltages to obtain a comparison result. The voltage regulation module regulates, based on the comparison result, an output voltage according to a predetermined rule to change the gate voltage.