Chronic myelomonocytic leukemia (CMML) is a clonal hematopoietic stem cell disorder characterized by peripheral blood monocytosis and myelodysplasia. Patients with CMML often present with concomitant autoimmune diseases (AIDs). However, the relationship between the pathogenesis of AID and CMML remains unclear, posing challenges for treatment selection. Several studies have suggested that the prognosis and treatment strategy in CMML patients with concurrent autoimmune diseases is of great significance. This article provides a comprehensive review of the literature on the types, possible mechanisms, prognosis, and relevant treatment progress of concomitant AIDs in CMML patients.