To evaluate serum prealbumin levels in chemotherapy-induced hepatotoxicity and to compare them with the other tests that are routinely used in children with cancer.We studied serum prealbumin levels before and 1, 3, 7, and 21 days after chemotherapy in addition to other tests (AST, ALT, ALP, total protein, albumin, total and direct bilirubin) in twenty-eight children with cancer receiving various combinations of chemotherapeutics. Serum ALT, AST, ALP, albumin and total and direct bilirubin were determined by enzymatic and photometric methods. Prealbumin was determined by an immunonephelometric method.Total protein and albumin were decreased, AST, ALT, ALP, and total and direct bilirubin levels were increased after chemotherapy and returned to the normal levels on the 21st day of chemotherapy, but these changes were not statistically significant. Prealbumin levels were significantly decreased on the first day of chemotherapy and returned to normal on the 21st day (p=0.001). The sensitivity and specificity of prealbumin were 28.5 % and 66.6 % on the third day and 40.0 % and 73.9 % on the seventh day, respectively. The positive and negative predictive values were 22.2 % and 73.6 % on the third day and 25.0 % and 85.0 % on the seventh day, respectively.Serum prealbumin levels seem not to be a good marker of chemotherapy-induced hepatotoxicity in respect to the other biochemical markers. On the other hand, hepatotoxicity of chemotherapy which may be fatal in severe cases and cessation of the ongoing chemotherapy may be warranted with the early decrease of prealbumin levels but it should be evaluated in larger group of patients before this conclusion (Tab. 4, Fig. 1, Ref. 18).