The invention provides an evolution analysis device and an evolution analysis method for the contents of network topics. The evolution analysis device for the contents of the network topics comprises a network event data collection device, a network event data pretreatment device, a topic content evolution analysis device and an output device. The evolution analysis method for the contents of the network topics includes the steps of network event data collection, network event pretreatment, similarity calculation, topic multi-center establishment, topic center renewal and output. A plurality of aspects of the contents corresponding to the topic can be found by the invention, and a multi-center structure is used for establishing a corresponding topic model so as to more accurately and comprehensively describe the topics; the dynamic evolution and development process of the contents of the topics can be displayed by the establishment and the renewal of the multi-centers of the topics, namely the whole process of generation, development, climax and ending of the topics. The method of the invention does not depend on the processing sequence of report, and can adapt to the circumstance of cross occurrence of news reports with different emphasises.