Can mechanical faults be controlled and eliminated at machine's run-time? Can a machine heal itself, as a living person or animal? What can be done before shutting down and overhauling a machine? Under the guidance of the systemics theory，borrowing the idea of “self-recuperation” therapeutic methdology in modern medicinal science, e.g.，the knowledge about the mechanisms of immunity, protection, compensation, regeneration, adaptation, etc., with the fault prevention and self-healing as the goal, this paper focuses on the study of the fault self-recovery principle and its engineering application, i.e. Fault Self-recovery Engineering (FSE), which can provide theoretical basis in developing a new generation of self-healing machine.