By studying and analyzing the preamplifier and main amplification circuits design in photoelectric conversion circuitry，the optimum handling way for circuit amplifying，filtering，noise reduction processing was given，the purpose of the useful signal separating and outputting from the noise was achieved.The various factors affecting the stability of performance parameters from the principle of photoelectric conversion circuit design to the final plate process were discussed.The criteria and the basis were put forward for the circuit device selec-tions，arrangement，wiring，and noise reduction methods and so on.