A sensitive and specific serum marker can greatly help in the early diagnosis of malignancy as well as in monitoring the treatment of cancer patients. The present work was initiated for determining serum levels of Total Sialic Acid (TSA), Lipid Bound Sialic Acid (LSA), Free Sialic Acid (FSA). Regan Isoenzyme (RI) and Lactate Dehydrogenase (LDH), so as to evaluate their value as potential tumor markers. Fifty patients with anemia and 78 patients with leukemia were studied. The leukemia group consisted of 32 cases of Acute Myeloid Leukemia (AML), 29 cases of Chronic Myeloid Leukemia (CML) and 17 cases of Acute Lymphatic Leukemia (ALL). The levels were compared with the values obtained from 88 healthy individuals. Compared to the healthy controls, all the biomarkers were significantly elevated in patients with anemia as well as in those with leukemia. However, in leukemia patients significantly higher levels of TSA, LSA, FSA and LDH were observed compared to anemia patients. TSA levels were significantly higher in AML patients compared to CML and ALL patients. LSA levels were also significantly higher in AML patients compared to ALL patients. LSA was the most sensitive (84.6%) while FSA and RI levels were the most specific (78.0%) markers for leukemia. The combined use of the markers showed increased sensitivity and specificity (100.0% and 98.0%, respectively). The study suggested that the biomarkers investigated might be used for differentiating anemic from leukemic conditions, however, more in-depth studies are indicated to assess their utility in classifying various leukemias.