Objective:This study aims to evaluate the sonographic features of phyllodes tumors of the breast (PTBs) and the cor-relation between sonographic and pathologic findings to improve the understanding of the disease. Methods:Sonographic findings of 85 PTBs from 83 patients were reviewed. The sonographic findings included the results of two-dimensional ultrasound and color Dop-pler flow imaging, elastographic features, and pathologic data. Results:Of the 85 lesions, 33 were the benign tumors, 28 were border-line, and 24 were malignant according to the pathologic diagnosis. Tumor morphology revealed that most masses were lobulated, with a clear-cut boundary, smooth verge, and inhomogeneous internal echo. Clear boundary was more common in the benign phyllodes tumors (χ2=12.721, P=0.002), and a cystic echo-free area was more commonly observed in these malignant tumors (χ2=9.677, P=0.046). LevelⅡandⅢsignals of the blood flow were observed in 75.3%of PTB cases. Of all lesions, only 26 were subjected to elasticity imaging, and the elastographic scores ranged from 2 to 3 in 88.5%of the cases (23/26). Conclusion:Conventional ultrasound and elastographic findings on PTBs exhibited definite characteristics. The border and cystic areas in the tumors can be used to differentiate between be-nign and malignant PTBs.