Objective: To determine the diagnostic utility of bone marrow aspirate in finding cause of hepatosplenomegaly. Study Design: Cross Sectional Descriptive study. Setting: Pathology Department of Khyber Teaching Hospital. Period: August 2017 to December 2017. Material & Methods: A total of 116 cases were referred to Pathology department for workup of hepatosplenomegaly during study period. Patients were subjected to bone marrow aspiration and biopsy. The cases were diagnosis was made and those where no specific diagnosis could be made were noted. Mean and standard deviation were used for quantitative variables. Frequency and percentages were used for qualitative variables. Results: Mean age of the study sample was 45±9 years (range 2 -64 years). There were 66 (56.89%) males and 50 (43.10%) females. No specific diagnosis could be made in 36 (31.03%) cases of hepatosplenomegaly. In remaining 80 (68.96%) cases a definitive diagnosis could be made on examining bone marrow aspiration. So the diagnostic utility of bone marrow aspiration examination was 68.96%. Conclusion: Bone marrow aspiration is valuable and diagnostically important tool for workup of cases of hepatosplenomegaly.