A method and system for managing automatic guidance of an aircraft during a complete engine failure. Said system includes means for monitoring engines so as to be able to detect a complete failure of the engines; means for detecting whether the aircraft is in flight; means for detecting whether the aircraft is in a different guidance mode from a guidance mode configured to make the aircraft descend with a reduced engine thrust and a fixed speed; and control means for automatically bringing guidance means of the aircraft into a guidance configuration compatible with the situation associated with the complete failure of the engines.