A method of updating software of terminals in a mobile broadcast system is provided. The method includes creating an update command for terminals of a particular model, the update command including update information; and broadcasting the created update command. The update information includes software version information and at least one of terminal manufacturer information and terminal model information. Further, the method may further include, before broadcasting the created update command, forcibly requiring terminals subscribe to an update service; and creating and broadcasting an update file for terminals of the particular model from among the forcibly subscribed terminals. The software of the terminals may be firmware.