This 35-year-old man presented with history of hemoptysis and breathlessness on exertion of 3 months duration. Examination revealed feeble left radial, brachial and carotid pulses. Chest radiograph showed a superior mediastinal mass and contrast enhanced computed tomography chest showed a large aortic arch with mass and compression effects. Endosonographic examination was suggestive of aortic aneurysm. During further evaluation, serum Venereal Disease Research Laboratory test was found to be positive in titers of 1:32. Treponema pallidum hemagglutination test was performed and showed positive titers of 1:64. Neurosyphilis was ruled out by normal cerebrospinal fluid examination findings. Patient was treated with injectable benzathine penicillin and aortic aneurysm repair was planned. The authors present a rare case of tertiary syphilis complicated with aortic aneurysm in this era of early use of highly effective antibiotics.