Background: Pancytopenia is a striking feature of much serious and life-threatening illness. The etiological diagnosis is essential for the clinical management and prognosis of the patient. Routine hematological investigations, examination of the bone marrow by aspiration and biopsy provides various details that help in understanding the pathogenesis of pancytopenia. Objective: To diagnose and know the etiology of pancytopenia through hematological evaluation and bone marrow examination. Setting and design: This is a cross-sectional study done in Department of Pathology, Sri Siddhartha Medical College and Hospital, Tumkur for a period of 18 months from 2016 to 2018. Material and methods: Patients belonging to all age groups found to have pancytopenia on complete blood count were included in the study. However, those who were on chemotherapy treatment were excluded. A total of 85 cases were included in our study. Primary hematological procedures and bone marrow aspiration were performed in all the patients, and trephine biopsy was done in 2 cases. Statistical data of age, sex, chief complaints, physical findings, peripheral blood examination, bone marrow aspiration findings and trephine biopsy in 2 were studied. Observations and results: Out of 85 patients, the most common cause of pancytopenia in our study was combined deficiency anemia (megaloblastic anemia and iron deficiency anemia) seen in 44 cases. Other causes were megaloblastic anemia seen in 27 cases, myelodysplastic syndrome seen in 7 cases, iron deficiency anemia seen in 3 cases, normal bone marrow in 3 cases and 1 case of malaria. Conclusion: Pancytopenia is a life-threatening illness. The physical findings and complete blood count provide valuable information in the patients with pancytopenia. Bone marrow study (aspiration/ biopsy) provides confirmation of the diagnosis.