Abstract: Objective To study the role of bone marrow cell morphology in diagnosis of Kala-azar by analyzing its misdiagnosis and missed diagnosis. Methods Clinical data about 3 kala-azar patients admitted to our hospital from 2011 to 2013 were retrospectively analyzed. Results Bone marrow puncture showed a large number of Leishmania in reticular and bone marrow cells from 3 patients who were thus diagnosed with kala-azar and treated. Conclusion The non-specific clinical manifestations of kala-azar are easy to lead to its misdiagnosis and missed diagnosis. Careful bone marrow cell morphology examination plays an important role in its etiological diagnosis.