Method for linking among related services in internet protocol television service system services and internet protocol television service system for materializing the same

PURPOSE: A method for linking related services among IPTV services and an IPTV system for realizing the same are provided to enable a user to confirm the broadcast progress of selected contents more conveniently. CONSTITUTION: An IPTV system for linking related services among IPTV services includes an EPG server and a client terminal. The PG server manages and provides an EPG including related VOD contents or additional service information for each program. The client terminal receives and stores the EPG, and displays a VDD service(300), a real-time broadcasting service and additional service information which are related to a program together with program information when displaying the EPG. The client terminal immediately provides a selected service when one of the services is selected by a client.