A method for updating a content of a given warning message emitted in an aircraft by a monitoring system in case of detection of a particular state of at least one monitored system of the aircraft, the method including a step of delivery of a plurality of modification information items to a selection tool, each modification information item defining a modification of a content of a warning message capable of being emitted by the monitoring system, the selection tool being capable of selecting at least one information item among the plurality of modification information items in such a way as to permit modification of the content of the given warning message.