Since improvement in the material, true aneurysms and pseudoaneurysm formations have become relatively rare complications after femoro-popliteal reconstruction with polytetrafluoroethylene (PTFE) grafts. We report a case of late graft rupture and pseudoaneurysm formation within the straight femoral part of a femoro-popliteal bypass with reinforced (PTFE-wrapped) Gore-Tex graft. The rupture occurred 7 years after implantation without history of direct traumatization. Intraoperatively the whole bypass showed macro- and microscopically visible deterioration of the wall with almost complete disruption at the site of the aneurysm. The graft had to be replaced completely. In conclusion, we recommend continuous long-term follow-up of these patients preferably with duplex ultrasonography.