In order to meet the requirements of real-time monitoring and post processing of the new RS-422 bus parameters in flight test data of a certain type aircraft,the algorithm design and implementation scheme for the new RS-422 bus parameters is proposed. By analyzing the communication protocol and data packet format of the new RS-422 bus parameters,the method of adjusting the frame structure and resetting the sampling rate is adopted to realize the analysis and reduction algorithm of the parameters,and the corresponding real-time monitoring and post processing software were designed. The software has been successfully used in the flight test of the aircraft,which provides a strong guarantee for the flight safety monitoring and data processing analysis.