The invention discloses a method and system for transmitting additional information in communication system, which includes the following steps. Terminal of the first client generates additional information according to their type, and adds them that contain the content and the type to the first speaking control-news to send to the centralized control-server. Receiving the first speaking control-news, the centralized control-server analyzes and obtains the first additional information. The system includes a centralized control-server and more than one user terminals, and at least one user-terminal includes a terminal processing module and an additional information add-module. The centralized control server includes a centralized control module and an analyzing module. |