In this study prognostic significance and clinical value of mutant p53 gene in bladder transitional cell tumors is investigated. In our clinic, between 1997-2000, transurethral resection was performed in 48 cases, 3 females (6%) and 45 males (94%) with the diagnosis of primary bladder tumor, age ranges between 30-81 years old (average 58.9 +/- 9.9). The patients whose pathology results were transitional cell carcinoma were gathered into two groups as p53 positive and p53 negative by immunohistochemical study. These cases who were followed 1-36 months were compared to each other for pathologic state, tumor grade, recurrence and survival. It's found out that mutant p53 accumulation is related to high grade and pathologic stage tumors. But it's concluded that p53 positivity doesn't effect recurrence and survival rates.