The reliability of serum total sialic acid (TSA), serum lipid bound sialic acid (LSA), and urinary sialic acid I creatinine ratio (TSAI Cr. ratio) as markers for bladder cancer for grading, staging and follow-up purposes was evaluated in I'O healthy controls and 70 patients with bladder cancer, 25 of them with superficial transitional bladder tumors were evaluated after treatment with TUR for follow up. We found that TSA, LSA and TSAI Cr. ratio levels were significantly higher in patients with bladder cancer (56.9 ± 8.9 mg I dl, 22.3 ± 2.3 mgl dl and 37.2 ± 16.1 ug/mg crcatininl! respectively) thal1 controls (48.8± 7.1 mg/dl, 16.9 ± 0.6 mg/dl and 11.9 ± 5.1 ug/mg creatinine respectively). There was no signi (icant di ffercncc between grade J, J1 and 111.... alsu bctwecll sl41ge 'i'a, T I & '1'2 ~lI1d slagL" '1'3 & '1'4 bladder cancer patients regarding LSA and TSA, but there was a significant difference between these grades and stages regarding urinary TSA I Cr. Ratio (20.1 ± 16.1,40.6 ± 14.4 and 47.8 ± 11.9 ug/mg creatinine in grade I, II and III respectively and 32.1 ± 12.1,46.4 ± 15.1 ug/mg creatinine in stage Ta, TI & T2 and stage T3 & T4 respectivly). These findings suggest that TSA and LSA can 110t be used for grading and staging of bladder cancer patients but urinary TSA/Cr. ratio cun be us..:d fOl' grading and staging of these patients. On compari!'"lon of superficial transitional bladder cancer patients before and alter treatment regarding the studied parameters, we found marked drop of urinary TSA/cr. ratio in post-treatment patients (36.2 ± 15.1 ug/mg creatinine before treatment versus 17.5 ± 5.3 ug/mg creatinine uncI' lreatment) in contrary with serum TSA and LSA. We conclude that: urine can be used as t!asily available physiologic fluid !,or evaluation of TSA I Cr. ratio by an easy