Pancytopenia is the simultaneous presence of anaemia, leucopenia and thrombocytopenia. The etiology ranging from non-neoplastic, neoplastic to fatal leukemias. The management and prognosis depends both on the severity of pancytopenia and on the nature of underlying etiology. Thus identification of cause is the key to appropriate management. To study the clinical presentations, diagnosis and evaluation of various causes of pancytopenia by hematological parameters including bone marrow aspiration. It was prospective study. One hundred and fifty cases of Pancytopenia evaluated clinically with hematological parameters and bone marrow aspiration in a Yashoda hospital, Malakpet, Hyderabad, during period of January 2014 to February 2017. Out of 150 cases, age of patients ranged from 2 to 85 years with a mean age of 43 years. There was male preponderance. Fever and generalized weakness was common clinical presentation. The commonest physical finding was pallor and splenomegaly on systemic examination. The commonest peripheral smear was dimorphic picture & commonest bone marrow finding was hypercellular marrow with megaloblastic erythroid hyperplasia. The commonest cause for pancytopenia was Megaloblastic anemia (34%) followed by Hematolymphoid malignancy (26.6%). This study showed that clinical history, detail primary hematological investigations along with bone marrow aspiration, biopsy imprint in cytopenia patients are helpful to diagnose and to rule out the causes of pancytopenia. Megaloblastic anemia is commonest cause of pancytopenia in most indian and continent studies. Present study also shows increase in incidance of HLH (Hemophagocytic lymphohistiocytosis) and MDS are among emerging causes of pancytopenia and nutritional diet rich in vit B12 and folic acid prevents majority cause of pancytopenia in india.