Aim: To analyse whether serum ferritin measured during early disease course can be used as a marker to indicate the severity which helps to triage and manage them appropriately. Material and Methods: The present hospital based prospective observational study comprised of 70 patients admitted in wards and ICU of Department of Medicine, Chattrapati Shivaji Subharti Hospital, Meerut satisfying inclusion criteria during the study period. Patients with NS1 positivity (Days 2–8) and/or positive IgM for dengue (Days 6–10) were considered to be dengue cases and those with other confirmed diagnoses were considered as ‘Other febrile illness’. The outcomes was measured as the course of illness whether patients develop warning signs or detoriate to severe dengue, condition at the time of final outcome (discharged healthy or death) and the length of hospitalisation. The study outcome of this study was the correlation between serum ferritin levels and the patient’s outcome. Results: Mean serum ferritin (ng/ml), platelet count and hospital stay (in days) was 1431.82±657.18, 18500±9011.67 and 3.46±5.19 respectively. Mean serum ferritin level and hospital stay (in days) was comparatively more among subjects suffering from severe dengue as compared to subjects having non severe dengue with statistically significant difference as p<0.05. Significant negative correlation was found between serum ferritin level and platelet count while significant positive correlation was found between serum ferritin level and hospital stay. Conclusion: Thus, in conclusion, serum ferritin level may be considered as a tool to predict the progress of dengue severity.