Abstract: ［Abstract］Objective　To discuss the diagnostic value of contrast-enhanced ultrasonography in differentiating benign and malignant tumor of pelvic cavity．Methods　From October 2014 to January 2016，abdominal ultrasonography or trans-vaginal ultrasonography were performed among outpatients and inpatients in the First Affiliated Hospital of Kunming Medical University. We found 62 cases with pelvic cavity tumors with 64 lumps， which were detected at cystic mass，cystic-solid mass，and solid mass in conventional ultrasonography. We made the diagnosis of all the lumps by performing contrast-enhanced ultrasonography，observing the infusion process and analyzing perfusion pattern，the intensity of perfusion and time intensity curve. By contrasting the diagnosis and the pathologic and long-term follow-up results，we classified the tumors into two groups， benign and malignant. Then we analyzed the time intensity curve and imaging parameters of the two groups．Results　Among the total 64 lumps， 43 was found in the group of benign tumor and 21 in the group of malignant tumor. Sixty-two were proved by pathologic results and 2 were proved by long-term follow-up results. Benign tumors showed that the infusion flowed from the peripheral to the center and enhanced equably and the vessels were regularly shaped. Malignant tumor showed that the infusion infiltrated from the center to the peripheral and enhanced quickly and unequally， and vessels were distorted. In the time intensity curve，group of benign tumors presented a gently slow raise and fall type， and group of malignant tumors showed a quickly raise and fall type．Rise time （RT） of malignant group（7.70±2.56s）was shorter than benign group（11.40±6.77s）（P＜0.05）．Peak intensity（PI）of malignant group（16.30±7.41dB）was higher than benign group （12.12±6.70dB） （P＜0.05）. Area Under the Curve（AUC） of malignant group（981.65±548.04 dB s）was bigger than benign group （715.22±651.04dB s）（P＜0.05）. No difference was found between two groups in Time to Peak（TP）and Mean Transit Time （MTT）（P＞0.05）. The sensitivity，specificity，positive and negative predictive value of contrast-enhanced ultrasonography were 95.2%， 93.0%，86.9%，and 97.5% respectively．Conclusion　Contrast-enhanced ultrasonography can show an eligible blood perfusion and vascularity of lumps. Analyzing perfusion pattern， time intensity curve，and other parameters can improve capacity of diagnosing and differentiating benign tumor and malignant tumor of pelvic cavity.