Streptococcus bovis endocarditis is a frequent cause of streptococcal endocarditis and is associated with colonic tumours. The tricuspid valve is very rarely affected and its involvement is a complication which can lead to a less favourable outcome. We report the seventh case of tricuspid valve endocarditis due to S. bovis, and the first, to our knowledge, to be associated with an atrial-septal aneurysm and a patent foramen ovale. The underlying medical conditions and predisposing factors for development of tricuspid valve endocarditis are described and interesting new echocardiographic data are presented. The current guidelines on antibiotic therapy for S. bovis tricuspid valve endocarditis are reviewed.