Background: Hematologic malignancies are of diverse incidence, prognosis, and etiology. Dhaka medical college hospital (DMCH) is a tertiary level hospital and dealing with patients attending from all over the country. We have analyzed data of patients present with hematological malignancy in our Out Patient Department (OPD). As Hematology Dept DMCH deal with patients referred from all over the country, its OPD data represents the picture of whole country. Methods: This is a retro-spective study of OPD patients with hematological malignancy in the department of Hematology of DMCH from January 2018 to December 2018. The diseases were diagnosed on the basis of bone marrow morphology or histopathology (Lymphoma) and or immunophenotyping & molecular genetics. Results: Total 5747 patients were treated in 2018 with the complaints related to hematological malignancy of which 4599 (80%) were old patients and 1148 (20%) were new patients. Among all the treated patients 1420 (24.7%) were female and 4327 (75.3%) were male. Among 1148 new cases 37 were AL(3%), 386 were ALL (34%), 265 were AML(23%), 32 were CLL (3%), 126 were CML (11%), 40 were HL (3%), 18 were MDS (1%), 76 were MM (7%), 168 were NHL (15%). Data shows variation in total number of new patients per month- 83 in January (7.23%), 96 in February (8.36%), 140 in March (12.20%), 98 in April (8.54%), 94 in May (8.19), 89 in June (7.75%), 98 in July (8.54%), 66 in August (5.75%), 99 in September (8.62%), 103 in October (8.97%), 98 in November (8.54%), 84 in December (7.31%) But it does not show any statistical significant frequencies of diseases according to months. Conclusion: We deal a lot of patients with hematological malignancy each year in DMCH. A good portion of them are of ALL because of monthly maintenance of ALL protocols. Analysis of new cases shows ALL, AML, NHL is most common three diseases encounter in OPD. OPD patients’ inflow does not show any significant monthly variation for any of the diseases.