We report the management of a case of thigh abscess with ruptured left superficial femoral artery mycotic aneurysm in a 91-year-old woman with significant comorbidity. The abscess culture grew Escherichia coli and Acinetobacter baumannii. Vascular reconstruction was not performed because the foot was viable with a heavily contaminated wound. The thigh wound healed with the help of vacuum-assisted closure. This is the first report of a ruptured mycotic aneurysm of the superficial femoral artery associated with Escherichia coli and Acinetobacter baumannii infection. This case demonstrates that resection of a mycotic aneurysm without vascular continuity is feasible, especially in frail patients.