Purpose. This study was conducted to evaluate the potential role of transvaginal color Doppler sonography (TVCD) in predicting response to concurrent chemoradiotherapy for locally advanced cervical cancer. Methods and Materials. Tumor vascularity was assessed using TVCD before the start of concurrent chemoradiotherapy in 21 patients (median age, 47 years; range, 31-75 years) with histologically proven locally advanced cervical cancer. The lowest resistance index (RI), lowest pulsatility index (PI), and highest peak systolic velocity (PSV) from central vessels within the tumor were recorded and used for analysis. All patients were clinically evaluated by physical examination and CT scanning after completing the chemoradiotherapy protocol. Complete clinical response (CR) was determined when no residual tumor was found. Partial clinical response (PR) was determined when the tumor volume had decreased more than 50%. Results. CR was achieved in 11 patients (52%), whereas 10 (48%) had PR. The initial median tumor volume was not statistically different between those with CR (26 cm3) and those with PR (28 cm3) (p = 0.71). RI was higher in those tumors with CR (median, 0.47) than in those with PR (median, 0.29) (p < 0.01). Likewise, PI was higher in tumors with CR (median, 0.81) than in those with PR (median, 0.41) (p < 0.01). No differences were found in PSV. The likelihood ratio for CR for tumors with a lowest RI of 0.35 or more was 2.7 (95% confidence interval, 1.8-3.6) and the likelihood ratio for CR for tumors with a lowest PI of 0.45 or more was 3.3 (95% confidence interval, 2.1-4.5). Conclusions. The results suggest that TVCD may be useful in predicting clinical response to concurrent chemoradiation in patients with locally advanced cervical cancer. © 2004 Wiley Periodicals, Inc.