Superior vena cava (SVC) syndrome is usually caused by extrinsic compression by malignant tumors, but para-aortic abscess can be responsible for this syndrome. We report a case of SVC syndrome caused by para-aortic abscess caused by Aerococcus viridans infection in a man who received orthotopic heart transplantation. A. viridans is a common saprophytic organism in hospital environments. There are reports of this organism being the cause of endocarditis, but no reports of it as the cause of a para-aortic abscess. This is a first report of A. viridans infection in organ transplant patients.