NSE, ferritin and LDH values have been evaluated in 15 fteuroblastoma cases in comparison with 14 healthy children. The mean NSE, ferritin and LDH values were found to be 112±65 ng/ml, 556±71 ng/ml and 980±560 U/L respectively in 15 patients with neuroblastoffla at diagnosis; the mean values of the same markers in the control group were±11ng/ml, 62±62ng/ml and 279±61 U/L respectively. Thus NSE (p<0.001), ferritin (p<0.02) and LDH (p<0.01) values in neuroblastoma patients were significantly higher than those of the controls. The difference in the mean values of NSE, ferritin and LDH obtained from 9 neuroblastoma patients at diagnosis and at the time of partial or complete response were found to be significant (p<0.05). The mean ferritin value obtained at the time of response were higher in these patients in respect to the control group (p<0.05), on the other hand the NSE and LDH values showed no difference in comparison to the control group (p>0.05). NSE, ferritin and LDH values in 55 serum samples obtained serially during the therapy in 6 patients were found to be correlated with disease activity (p<0.05).