Background: Dengue infection occurs in epidemic and can be fatal. Bleeding due to thrombocytopenia and hypovolemic shock due to capillary leak is the predominant clinical feature. Bone marrow suppression as a cause of thrombocytopenia and neutropenia is well documented. This is generally recognised as decrease in the count of formed elements in the peripheral blood. However, relation of such a phenomenon with the serological stage of the disease is less studied. Aims and Objective: We aimed to quantify the magnitude of peripheral cell line suppression in relation to serological status of dengue illness. Materials and Methods: This was a retrospective study. Dengue infection was diagnosed by clinical and serological parameters.The proportion of patients with peripheral cell line suppression and their association with the different serological phases was described. Results: Records of 219 Dengue positive patients were analysed retrospectively. Most common serological status was positive IgG which was noted in 68.9%, this was followed by NS1 antigen positivity in 39.7% of the patients. Around 40% of the patients had peripheral cell line suppression of two or more formed elements at the time of diagnosis. Sixty-four percent of them had low platelet and WBC counts. All the three formed elements were decreased in 14% of our patients. Of these, 23% were in the initial phase of the illness and 33.3% during post primary phase. Conclusion: Decrease in the formed elements in the peripheral blood suggesting bone marrow suppression is seen in nearly 40% of the patients with Dengue infection at the time of diagnosis. This was highest during post primary phase followed by initial phase of the illness.