Abstract: As an important step of content based news video retrieving and information mining，semantic unit segmentation has attracted many researchers’ interests.This paper focuses on a new method of news video stories segmentation which is based on the announcer identification.Firstly，the voiceprints including acoustic perception characteristics of each announcer are extracted，and their Gaussian mixture models are trained，then the audio shots of announcer and not-announcer are detected by the KL divergence method，at last the unit segmenting is carried on under the guidance of video topic caption frames and special structure knowledge of news program.Finally the 92.58% recall and the 96.02% precision are achieved during more than 2 hours’ experiment.