The research on the remote fault-diagnosis system in existence is often centered on the diagnosis model and method. Here, following the viewpoint of information theory and system theory and taking the fault information as a beginning, it is pointed out that the remote fault-diagnosis system is a complete process of information processing. Through researching on and analyzing several ways of information acquiring, a general model of information acquiring is presented. Moreover it is pointed out that reasonable information optimizing, resource configuring and mission transporting are important and necessary on condition that the network band-width is limited and the fault information is of huge amount. The present research shows that the studying of fault information is the basis or core of the system in remote fault diagnosis, and it is helpful to the effective and reasonable operation of the system to consider problems from the viewpoint and method of information processing.