Objective: To investigate the diagnostic value of IOTA simple rules,Caruso score alone and in combination on benign and malignant ovarian tumors.Methods: 167 cases of ovarian tumors diagnosed and treated in our hospital were retrospectively analyzed(62 malignant cases,105 benign cases),Collected various ultrasonic morphological index and color Doppler flow index,without knowing the pathological result, we used IOTA simple rules, Caruso score respectively and the combination of both for the differential diagnosis of benign and malignant ovarian tumors. Results:Five blood flow indicators of color Doppler were statistically significant（P＜0.05）, Caruso score of malignant ovarian tumor was significantly higher than the benign,the difference was statistically signifficant（P＜0.05）.The applicable rate of IOTA simple rules was 78.4%, IOTA simple rules, Caruso score and the combination of both were used in the diagnosis of benign and malignant ovarian tumors,the sensitivities were 91.7%、87.1%、93.5% , the specificities were 95.2%、79%、91.4%, the positive predictive values were 91.7%、71.1%、86.6%, the negative predictive values were 95.2%、91.2%、96%,the diagnostic coincidence rates were 93.9%、82%、92.2%. Conclusion: Ultrasonic morphological characteristics and color Doppler flow characteristics of benign and malignant ovarian tumors are different. IOTA simple rules and Caruso score are reliable methods to make a differential diagnosis of benign and malignant ovarian tumors,But IOTA simple rules can not diagnose all tumors. Caruso score has lower diagnostic efficiency than IOTA simple rules ,the combination of the two methods to diagnose ovarian tumors is the best.