Disclosed are a system for providing a broadcast service and a method for providing a broadcast service. An example of the method for providing a broadcast service includes receiving a broadcast signal including broadcast contents and side information to provide the broadcast contents; reading out at least one of objects from question data that is input regarding the broadcast contents and primarily analyzing the read-out object to read out a subject of the question data; searching a social media site and collecting social media data relating to the subject from the searched social media site; secondarily analyzing the social media data and the side information in the broadcast signal on the basis of the subject; and configuring answer data corresponding to the subject using the analysis result and providing the answer data, and provides information which is extended and varied in real time.