Niemann-Pick disease has an autosomal recessive inheritance pattern and occurs due to a deficiency of a lysosomal enzyme, sphingomyelinase. It causes variable clinical signs and symptoms such as hepatosplenomegaly, delayed milestones, and peripheral cytopenia due to bone marrow involvement. Here, we report a case of a child who presented with hepatosplenomegaly and pancytopenia, who was later found to have Niemann-Pick disease on bone marrow examination. This case highlights the case presentations of this rare disease and the importance of bone marrow trephine in prompt diagnosis and management of a patient.