Provided are a message processing method, a device, a gateway, a Set-Top Box (STB) and an Internet Protocol Television (IPTV) system. The gateway is connected with a network where the STB is located and connected with a network where a terminal is located, can communicate with the STB and the terminal, and is configured to forward a message between the STB and the terminal. The disclosure solves the problem of being unable to interact with an STB if the matched remote control is lost or damaged, and achieves interaction with the STB through a terminal, thus providing a different mode of interaction with the STB, and improving user experience.