The global burden of cancer is gradually rising. In our context we are also facing the same problem. Hematological malignancies (HMs) are important component of cancer. Early diagnosis and proper treatment at right time, a good number of HMs patients can be cured or lengthening the survival period. For this purpose a proper diagnostic criteria should be developed in our settings. This research work is carried out to find out the clinicopathological findings of HMs in our population. This was a cross-sectional descriptive type of observational study conducted in the Department of Medicine and Hematology of Mymensingh Medical College Hospital, Bangladesh from July 2016 to June 2017. Total 45 patients were purposively selected on the basis of inclusion and exclusion criteria with a view to observe the clinical and laboratory findings. Mean age of the patients was 44.5 years. Highest average age (70 years) was found in chronic lymphocytic leukaemia (CLL) and lowest (29 years) in acute lymphoblastic leukaemia (ALL). Majority of the respondents were male in all HMs except in non-Hodgkin's lymphoma (NHL) where male-female ratio was 0.3:7. Among male most of them were farmers or day laborers and most of the females were housewife. Almost all patients were exposed to single or multiple exposures like smoking, betel nut, betel leaf, tobacco leaf, fertilizer or pesticides. Acute myeloblastic leukaemia (AML) was the leading HMS with 31.11% representation followed by non-Hodgkin's lymphoma (NHL) 20%, Hodgkin's lymphoma (HL) 15.56%, acute lymphoblastic leukaemia (ALL) 11.11%, chronic myeloid leukaemia (CML) 11.11%, multiple myeloma (MM)6.67% and chronic lymphocytic leukaemia (CLL) 4.44%. Duration of symptoms was vary from 2 days to 5 years. In acute leukaemia duration was short (average 2 months). Common clinical findings were anaemia (95.5%), fever (80.0%), hepatosplenomegaly (42.2%), lymphadenopathy (40.0%), bony tenderness (22.2%) and bleeding manifestations (15.5%). Some uncommon findings were also reported like menorrhagia, facial nerve palsy, arthritis and disorientation. Common laboratory abnormalities were high ESR, anaemia, leukocytosis, thrombocytopenia and immature cell in PBF especially in acute leukaemia. Clinical suspicion along with history of positive exposure indicates strong possibilities of haematological malignancies. It should be kept in mind that haematological malignancies may also present with some isolated uncommon findings.