Disclosed is a differential transimpedance amplifier (TIA). In the differential TIA, an input end of the first source follower is coupled to the first output end of a first differential amplification circuit. The output end of the first source follower is coupled to the second input end of a second differential amplification circuit with feedback and a first feedback resistor. The input end of a second source follower is coupled to the second output end of the first differential amplification circuit. The output end of the second source follower is coupled to the first input end of the second differential amplification circuit with feedback and a second feedback resistor. A photo diode and a dummy diode are coupled respectively to two input ends of the first differential amplification circuit.