Abstract: In this research, Kalman filtering mathematical methods are introduced to determine xylene isomers and the differentiation for xylene isomers chromatographic overlapping peak under certain experimental condition was studied. N2000 chromatographic working-station are used to collect data. Then, these data are made to be some matrix. The result is obtained to operate these matrix in a Kalman filtering program. The result shows that the average rate of recovery of every component reaches 91.1%～107.5% and RSD is 3.6%～8.3%.

Key words: xylene isomers； the differentiation of chromatographic overlapping peak； Kalman filtering method；