A method for analyzing faults present on a platform includes the following steps: (a) providing a table of correspondence between a plurality of observable symptoms on the platform (10) and the fault modes capable of creating each observable symptom; (b) measuring the observable symptoms present on the platform (10); (c) establishing at least one family of faults, including determining a list of fault modes capable of creating, alone or in combination, all of the selected present symptoms, placing each given fault mode of the group in a fault family, and grouping all of the fault modes capable of creating at least one selected present symptom shared with the given fault mode together in the same fault family as the given fault mode. The method is applicable to fault analyses on aircrafts.