An Internet Protocol (IP) TeleVision (IPTV) service provision method and system is provided for providing both fixed and mobile device users with IPTV services. The IPTV service provision method of the present invention includes establishing, when a Mobile-IPTV terminal function (M-ITF) including a first Open IPTV Terminal Function (OITF) having a plurality of functional entities and an embedded gateway having a plurality gateway functions detects a gateway function of an IPTV Terminal Function (ITF) including a second OITF having a plurality of functional entities and a plurality of gateways, a link with the gateway function of the ITF; disabling the embedded gateway; requesting a service provider network for an IPTV service via the gateway function of the ITF; and establishing a service link with the service provider network to received the IPTV service.