The invention concerns a system for detecting a rupture inside a portion (6; 12; 13; 15) at least of one structure, delimited by a first (7; 16) and a second (7; 17) reference points of the structure, said portion having a predetermined stiffness in the absence of rupture and being subjected to a tensile or compressive stress (F). The method includes the following steps: detecting at least one length variation inside the portion of the structure, in response to a variation (?F) of the tensile or compressive stress applied to said portion; deducing from the detected variation length, the existence or not of a rupture inside said portion of the structure.