Objectives: Hematological changes are among the most common complications encountered in malaria. This study analyzes and statistically evaluates the hematological changes as a diagnostic test for malaria in patients with acute febrile illness and whether these could guide the physician to institute specific antimalarial treatment. Methods: The present study was an observational study, conducted from January to December 2012. A total of 723 patients presenting with acute febrile illness at our hospital were evaluated. A complete blood count and malarial parasite microscopy were performed for each patient. Results: The findings showed that 172 out of 723 patients (24%) were diagnosed to have malaria by positive smear report. There were 121 males and 51 females with a male to female ratio of 2.3:1. Maximum number of cases were seen in the 20-30 years age group. There was a statistically significant reduction in hemoglobin (p<0.005), platelet count (p<0.001) and total leukocyte count (p<0.001) levels in patients with malaria compared to those without the disease. Likelihood ratios for a positive result of platelets (6.2) and total leukocyte count (3.4) was relevant as compared to hemoglobin (1.61) and Red cell distribution width (1.79). The negative predictive values for hemoglobin (79%), total leukocyte count (86%), platelets (94%) and Red cell distribution width (93%) were significant. Red cell distribution width values were found to be higher in patients with malaria than in patients without malaria (p<0.001). Conclusion: This study revealed that routinely used laboratory findings such as hemoglobin, leukocytes, platelet counts and even red cell distribution width values can provide a diagnostic clue in a patient with acute febrile illness in endemic areas, thus increasing the probability of malaria and enhancing prompt initiation of treatment.