Objective: To determine whether p53 expression and ploidy were related to traditional prognostic indicators in patients with ovarian cancer. Methods: Tumour material (n=188) was analysed regarding flow cytometric DNA ploidy and the immunohistochemical p53 expression. Pearson correlation, Fisher's exact test, Cox's regression analysis and Kaplan-Meier survival tests were used, as appropriate. Results: p53 accumulation and aneuploidy were more frequent in patients with serous histology, FIGO advanced stage, who were poorly graded, and had positive peritoneal cytology and tumour recurrence. Patient's age, stage, grade, tumour residue, positive peritoneal cytology, and overall survival rate correlated with p53 accumulation and DNA ploidy. No association of histological subtype with p53 and DNA ploidy was observed. p53 was also strongly related to DNA ploidy. p53 and DNA ploidy were found to be important determinants of recurrence in univariate analyses. Of the factors analysed, p53 was the significantly stronger independent predictor factor for tumour recurrence. Utilizing survival as the endpoint for multivariate analysis, age, grade, tumour residue, and DNA ploidy were independent prognostic indicators. Conclusions: p53 expression and DNA ploidy were related to FIGO stage, grade, peritoneal cytology, tumour recurrence and overall survival. p53 was the stronger independent determinant factor for tumour recurrence, while DNA ploidy was the stronger independent prognostic factor for overall survival. Since DNA ploidy and p53 accumulation were significant factors for overall survival when submitted to univariate and multivariate analysis, they can be useful factors when making a prognosis.