Uterine fibroid is the most common benign tumor in female reproductive system and also the most common benign tumor in human body, very few fibroids will undergo degeneration. The degeneration of uterine fibroids can be divided into two categories: benign degeneration and malignant degeneration. The more common uterine fibroids degeneration is as follows: 1. vitelliform degeneration, which is the most common kind of degeneration of uterine fibroids, and it is the result of ischemia and necrosis of uterine fibroids, the degeneration area is edematous, and the edema is lost in the swirling or striped structure, the boundary is clear, and it shows in the ultrasonic image as hypoechoic area, and the irregular echo-less area is seen in the tumor, with slightly enhanced echoes in the posterior wall. 2. cystic degeneration. Cystic degeneration, this kind of degeneration is further developed from vitelliform degeneration, with necrosis and liquefaction of tissues, forming multiple cystic cavities separated by connective tissues, or fused to form a large cystic cavity, with colorless fluid inside the cyst, and the ultrasound image shows irregular echo-less areas in the degenerated area, and echo enhancement in the posterior wall.