he a prospective study of the effect of body weight of 70 patients with lymphoma on the levels of serum sialic acid forms, total sialic acid, bound sialic acid, free sialic acid and lipid sialic acid were measured. The results were compared with those obtained from control groups which consisted of 50 person of matched age and sex. Objective: To determine the influence of body weight on the serum sialic acid forms. Methods: The patients were categorized into four groups according to the certain statistical methods. The first group comprised 24 patients who have weight 5-20Kg range. The second group comprised 13 patients who have weight 21-40Kg range. The third group comprised 12 patients who have weight 41-60Kg range. The fourth group comprised 21 patients who have weight >60Kg. Results: Significant elevations (P<0.005) of total sialic acid, bound sialic acid, free sialic acid, and lipid associated sialic acid (TSA, BSA, FSA, and LSA respectively) levels were seen in all groups of lymphoma patients when compared with those of the healthy subjects. Total serum protein was decreased significantly (P<0.005) and TSA/TP, BSA/TP, FSA/TP, and LSA/TP ratios raised significantly (P<0.005) in the cancer patients in comparison with those of the healthy individuals. Conclusion: Sialic acid is not specific marker for detecting lymphoma patients.