Voice of plural participants during a meeting is obtained and dialogue situations of the participants that change every second are displayed in real time, so that it is possible to provide a meeting visualization system for triggering more positive discussions. Voice data collected from plural voice collecting units associated with plural participants is processed by a voice processing server to extract speech information. The speech information is sequentially input to an aggregation server. A query process is performed for the speech information by a stream data processing unit of the aggregation server, so that activity data such as the accumulation value of speeches of the participants in the meeting is generated. A display processing unit visualizes and displays dialogue situations of the participants by using the sizes of circles and the thicknesses of lines on the basis of the activity data.