This paper concerns the behaviour of a structural ceramic matrix composite, SiCf-SiC, irradiated with swift xenon ions, with a fluence of up to 10(15) Xe cm(-2). Damaged materials were investigated by transmission electron microscopy along the beam penetration. Damages are mainly located at the fibre-matrix interfaces, where amorphous zones are evinced in the turbostratic carbon interphase, as well as in the fibres themselves. Latent tracks have also been observed in the fibre close to the fibre-matrix interface.