Caecal diverticula are rare, representing the 3.6% of colonic diverticula. They may have congenital origin and remain asymptomatic, presenting as an accidental finding. We present a case of a 42-year-old Caucasian woman, admitted with a 12-h history of sudden onset of sharp right iliac fossa pain, anorexia, and nausea. There was leukocytosis (23.49 × 10(3)/μl) and increased C-reactive protein (11.76 mg/dl). CT scan showed an inflamed appendix. At laparotomy, a diffuse caecal phlegmon with an inflammatory solitary caecal diverticula was found. A limited right hemicolectomy was performed. Histological examination confirmed the caecal diverticulitis without malignancy. Post-operative period was uneventful. Three months later, endoscopy showed no diverticula or other pathologies. Solitary caecal diverticulum is very rare, but surgeons must bear this in mind in case of pain in right iliac fossa.