Splenic rupture is a rare but serious iatrogenic complication of colonoscopy, potentially leading to hemodynamic instability. When common complications such as post-polypectomy syndrome and perforation are excluded, physicians must maintain a high level of suspicion for splenic injury, particularly in patients presenting with abdominal pain after the procedure. This report describes an emergency splenectomy performed on an 80-year-old male following a routine colonoscopy. Seven hours of post-procedure, the patient presented abdominal pain, syncope, sweating, and hypotension. Computed tomography imaging revealed a ruptured spleen with a 7-cm parenchymal hematoma, a significant blood halo surrounding the liver, and a large blood accumulation in the pelvis. The patient underwent an emergency splenectomy and was discharged 6 days later without complications.