Abstract: In order to meet the requirement of the fast luminosity monitor system of Beijing electron-positron collider (BEPCⅡ), a high-speed bunch-by-bunch luminosity signal processing and displaying system was designed. The techniques such as fast signal amplification, discrimination, long-distance signal transmission, anti-coincidence event judgment, counting for each bunch and ping-pang storage were involved effectively. The preliminary test result shows that the system can process and display the luminosity signals for bunches with 4 ns separation.