The spectrum of organisms causing native valve endocarditis is changing. Despite an increasing incidence of infections caused by gram-negative organisms, they remain a rare cause of native valve endocarditis. Escherichia coli is especially uncommon. We describe the case of a 47-year-old man with no previous history of cardiac problems, who presented with culture-positive E coli endocarditis of his native aortic valve. His complicated clinical course necessitated emergent valve replacement, emphasizing the virulence of this organism. The high mortality rate and significant morbidity associated with this entity necessitates aggressive medical management and early surgical intervention.