Background: Hematological disorders are quite common in all age groups. The most common presentation is Anemia. Bone marrow examination is a necessary adjunct to the study of diseases of the blood and how a correct diagnosis can be made. The study aimed to analyze the various causes of haematological disorders. Aim of the study: To study the spectrum of haematological disorders on bone marrow examination, to know the age and sex incidence and to determine the causes of pancytopenia. Materials and Methods: This was a retrospective study carried out in the upgraded department of pathology, Osmania General Hospital, Hyderabad, Telangana from May 2022 to April 2023. Bone Marrow Aspiration of 100 cases of suspected haematological disorders was carried out complete detailed history, examination and complete blood counts were recorded. Results: In this study, out of 100 cases, the age of patients ranged from 11 to 80 years with a mean age of 31.8 years with male preponderance (1.5: 1). Most of the patients clinically presented with fever, easy fatiguability and generalized weakness. The most common cause is Megaloblastic Anemia (45%), followed by normal bone marrow study (22%), hypocellular marrow (12%), acute leukaemia (10%), idiopathic thrombocytopenic purpura (6%), multiple myeloma (4%), granulomatous disease (1%). Conclusion: The current study showed the usefulness of bone marrow aspiration in the evaluation of bone marrow in routine haematological disorders and for understanding disease progression. Keywords : Bone Marrow Aspiration, Haematological disorders, Megaloblastic Anemia.