This study was conducted on 93 patients, diagnosed or clinically suspected to have TCC of the urinary bladder attending to the Urological Department in Saddam Medical College University Hospital, Al-Shaheed Adnan Teaching hospital & Al-Yarmouk Teaching Hospital during the period from 21/July/2001 to 13/Jan./2002. 76 were males & 17 females with a mean age of 59 years. Urine cytological examination was done to those patients to detect malignant cells with the identification of the degree of differentiation, if possible, the cytological findings were correlated with the histopathlogical findings. Quantitative cytophotometric evaluation of nuclear DNA contents was done on malignant transitional urothelial cells in urine sediment smears obtained from those patients with a positive urine cytological examination after staining with feulgen reaction .100 microspectrophotometric readings were taken from each cytological grade, which were recorded as optical densities. Urine cytological examination has a sensitivity of 87.7%, specificity of 100% with an overall accuracy of 78% in the detection of TCC of the urinary bladder. DNA quantitation results were consistent with the cytological grades, as the DNA contents were increased with the increase of the grade of the tumor. So urine cytological examination has an acceptable sensitivity & specificity in the diagnosis of TCC of the urinary bladder & DNA quantitation can be used as a complementary investigative tool with urine cytological examination to confirm the diagnosis of TCC of the urinary bladder & to identify the grade of the tumor.