A fingerprint detection circuit and an electronic device are provided. The fingerprint detection circuit is configured to apply an excitation signal to a finger so as to generate a finger capacitor, and the fingerprint detection circuit includes: a signal amplifier having a negative input terminal connected with the finger capacitor, a positive input terminal connected with a voltage reference terminal, and an output terminal to output an output voltage according to a capacitance value of the finger capacitor; a capacitor; and a switch unit connected with the negative input terminal and the output terminal of the signal amplifier respectively, and configured to control the capacitor to be connected between the negative input terminal and the output terminal of the signal amplifier, such that the output voltage has a non-linear relationship with the capacitance value of the finger capacitor.