Splenic injury is a rare but serious complication of colonoscopy. Since the mid-1970s, 68 splenic injuries during colonoscopy including our 2 cases have been described. With the increasing use of colonoscopy, endoscopists, surgeons, and radiologists are more likely to encounter this unusual complication. Any cause of increased splenocolic adhesions, splenomegaly, or underlying splenic disease might be a predisposing factor for splenic injury during colonoscopy. However, it can occur in patients without significant adhesions or underlying splenic pathology. The diagnosis is often described in the literature as delayed, because many physicians are not aware of this complication of colonoscopy. Although computerized tomography is highly sensitive, knowledge of this complication is the best tool to aid in early diagnosis. Patients with abdominal pain, hypotension, and a drop in hematocrit without rectal bleeding after colonoscopy should be suspected of having splenic injury. Early recognition and interdisciplinary management are required to assure successful management of this potentially life-threatening injury. Patients with hemodynamic instability most often undergo surgery. We present 2 cases of splenic injury secondary to colonoscopy that required splenectomy.