One thousand postmenopausal women were examined prospectively with transvaginal ultrasound. Seven hundred forty-three (74%) were asymptomatic and presented for screening. Data were analyzed to determine the accuracy of this new modality. Eighty-three women had surgery, and 29 malignant neoplasms were found. Color flow was identified in 27 of 29 malignant tumors and 35% of benign masses. A cutoff value of 0.41 for the Doppler resistance index in the feeder vessels had the best discriminatory value; sensitivity and specificity were 96 and 95%, respectively, for separating benign from malignant neoplasms. Positive and negative predictive values were 96 and 95%, respectively. Morphology alone had poor sensitivity, but when combined with Doppler indices, the sensitivity improved to 90% and the positive and negative predictive values were 90 and 96%, respectively. The results of this study suggest that in the postmenopausal ovary, transvaginal B-mode imaging, color flow, and Doppler indices satisfy criteria as tests that may be sensitive and specific enough for application in a screening program.