Abstract: In this paper,we describe the development of readout electronics for two channels CZT detectors,including the charge sensitive preamplifier and signal processing circuit.The latter includes the differential amplifier,pole-zero cancellation circuit,filter circuit,fine-tuning circuit,baseline restoration circuit and summing amplifier.After the signal from ¹³⁷Cs（662keV） source being through differential amplification,pole-zero cancellation and filter circuit,the output signal is about 260mV and the signal duration is within 10μs.After the signals from the two channels being summed through the summing amplifier,the signal to noise ratio is greater than 15:1.The preliminary results show that for the ¹³⁷Cs source,the detection efficiency of the two parallel CZT detectors with this signal processing system is as many 1.74 and 2.2 times as the single ones,respectively,and the energy resolution（FWHM） is similar to that of the single one.