Splenic rupture can be categorized into two groups: traumatic and atraumatic. Traumatic rupture is frequently associated with blunt abdominal trauma, while atraumatic splenic rupture (ASR) is more uncommon and has been associated with both benign and malignant hematological disorders. In general, most cases of splenic rupture are managed with splenectomy, which carries significant mortality and morbidity; more recently, splenic artery embolization (SAE) has become a mainstay of management particularly after traumatic rupture. We describe a patient with chronic myelomonocytic leukemia (CMML) who presented to the emergency department for acute abdominal pain and was found to have an ASR. He underwent partial SAE, with postoperative complications of leukocytosis and tumor lysis syndrome (TLS) requiring rasburicase and allopurinol. On follow-up in clinic 2 months post-discharge, the patient was doing well on hydroxyurea, without need for further intervention at that time. In patients with hematologic malignancies presenting with abdominal pain and splenomegaly, it is important to consider ASR as a rare, but possible complication. To our knowledge, this is the only reported patient treated with SAE in the context of ASR from CMML, demonstrating that SAE can be an effective nonoperative strategy for treatment of CMML-associated ASR. This case report also highlights postoperative complications and management in this patient population, specifically a profound leukocytosis and TLS, for which close monitoring should be performed.