Objective: The aim of this study is to find out the common causes that lead to pancytopenia in our population specially in the province of Punjab. Material and Methods: This is a cross sectional study that was conducted at Chughtai Institute of Pathology, Lahore. The duration of the study was from June 2020 to December 2021. A total of 210 patients were included in the study. A through history was taken and complete physical examination was done prior to the bone marrow biopsy procedure. Peripheral blood sample was run on Sysmex XN 9000 automated hematology analyzer. Bone marrow aspirate and trephine biopsy were thoroughly examined and immunohistochemical stains were applied where required. The data was analyzed using SPSS 23.0 and frequencies were calculated. Results: Most common causes of pancytopenia in our study were megaloblastic anemia (18.1%) followed by aplastic anemia (12.9%), immune mediated causes (12.4%), acute myeloid leukemia (11%), hypocellular marrow (9%) myelodysplastic syndrome (6.2%), hypersplenism (5.2%) and Precursor B acute lymphoblastic leukemia (5.2%) (Fig. 2). Other causes include B cell non-Hodgkin lymphoma (4.8%), mixed deficiency anemia (4.2%), hypersplenism (3.8%), Gaucher’s disease (1.4%), infections (1%) and other miscellaneous causes (4.8%). Conclusion: The study conducted at our institute showed that majority of patients had benign causes (69.2%) leading to pancytopenia, the most common cause being megaloblastic anemia. Malignant causes constitute only a minority of cases of pancytopenia. Key Words: Bone marrow biopsy, Frequency, Pancytopenia