This study was directed to the role of p53 gene in the carcinogenesis of thyroid carcinomas and to the correlation between p53 gene and the clinicopathological characteristics of the cancer. Single-stranded conformation polymorphism of PCR was used in detecting p53 gene point mutations in exons 7, 8. The result showed that ten of thirty-one thyroid carcinomas had mutations in exons 7 and 8 (32.3%). The frequency of p53 gene mutations was significantly higher in relapse group than in no relapse group (P < 0.01). No statistically significant differences in p53 mutation were found relating to metastasis, histological type and differentiation (P > 0.05). These data suggest that the mutation of p53 gene may play an important role in thyroid carcinoma and the mutations of p53 gene be associated with the prognosis of thyroid carcinoma.