The invention relates to a system and method for carrying out global information transmission by utilizing a navigation satellite. Information transmission is carried out by utilizing the existing navigation telegraph message transmission system of the navigation satellite; on the premise of not changing a navigation telegraph message transmission format and a transmission rate, an information injection hidden transmitter is additionally arranged in the front of a navigation telegraph message transmitter; hidden transmission of user data is realized based on an information hiding method; normal use of a navigation positioning satellite system is not influenced; the practical functions of the navigation positioning satellite system are expanded; multiplexing of a navigation satellite channel is realized; a broadcast communication manner facing to the coverage area of the navigation satellite is also provided; by means of the system, any individual user can receive information through a commercial civilian navigation satellite user receiver; any hardware cost is nearly unnecessary; and for example, real-time and non-real-time text transmission and non-real-time image transmission can be provided in border areas, foreign travel areas, areas without other communication manners and areas, where communication manners are inconvenient to use.