The present solution relates to a data transmission method and system of a satellite set top box. The method comprises: by means of a coaxial cable between a satellite set top box and an antenna tuner, loading a 22 KHZ carrier signal on the coaxial cable for data transmission, and encapsulating and converting parameter data of the satellite set top box, so that the parameter data can be adjusted to the 22 KHZ carrier signal to be transmitted to the turner, thereby achieving the transmission of parameter data of the satellite set top box to the turner. The antenna can accurately obtain the parameter data of the satellite set top box after performing parsing by using an external data parsing device; with accurate location adjustment and search, a user is able to accurately adjust the location of an antenna. The searching efficiency and result is very accurate so that it is convenient for a user to use, and great convenience is brought to the user.