To further improve the accuracy and detection efficiency on the leakage monitoring with 13 N of pressurized water reactor, a five-detectors and ten coincidence circuit is designed. The circuit adopts STC89C52 single chip microcomputer as the core part of counting processing, and the measurement result are displayed by the computer. The experimental results show that the main performance indexes of this coincidence circuit satisfy the design requirements and it is applicable to the leakage monitoring with 13 N of pressurized water reactor. © 2017, Editor...