Abstract: Objective 　To determine the utility of DNA flow cytometry as a prognostic indicator for risk of recurrence and survival in patients with locally advanced squamous cervical carcinoma. Methods 　DNA flow cytomet ry was performed to determine ploidy, S phase fraction (SPF), and proliferative index ( PI) in 68 women with stage ⅢB squamous carcinomas of the cervix treated by radiotherapy (RT) . Sixty-eight tissue samples were obtained by punch biopsy from cervical primary tumor before RT. Flow-cytometric results, along with other known prognostic variables for risk for recurrent disease and survival, were analyzed using COX regression proportional hazards model, and survival curves were generated by the Kaplan Meier method. Results 　Of 68 samples, DNA ploidy patterns were 36 (52. 9 %) diploid and 32 (47. 1 %) aneuploid. The mean values of SPF and PI were 7. 49 ±2. 91 and 12. 89 ±3. 75 respectively. Thirty of 68 patients (44. 1 %) experienced recurrence during the follow-up . Aneuploid patients had lower 5-year recurrent free survival than those with diploid pattern (35. 2 % vs. 52. 7 %; P < 0. 05) and high SPF group had lower 5-year recurrent f ree survival than low SPF group as well (25. 3 % vs. 56. 6 %; P < 0. 05) . Multivariate analysis confirmed that only SPF and tumor size were the significant factor for 5-year recurrent free surval ( P < 0. 05) . Conclusion 　DNA ploidy and PI are not independent prognostic factors for tumor recurrence ; however, a high SPF warrants further investigation as a potential prognostic indicator for risk of recurrent disease in patient s with squamous carcinoma of the uterine cervix.