The association of Streptococcus bovis endocarditis with colonic neoplasia is classically described and exceeds 50 percent. The prevalence of Streptococcus bovis in fecal cultures from patients with carcinoma of the colon is significantly increased (56%) as compared to that in controls (10%) and also in patients with inflammatory bowel disease (28%). Streptococcus bovis endocarditis is relatively benign, but it stresses the frequency of the associated colonic carcinoma, requiring colonoscopy and making the treatment of the high-risk lesion mandatory. The article covers a literature review and a case report.