[Abstract] Objective To explore the value of ultrasound in diagnosis and monitor of placental chorioangioma. Methods 13 cases with placental chorioangioma which were confirmed by pathology after delivery were reviewed. The prenatal ultrasonographic manifestations and pregnancy outcomes were analyzed retrospectively. Results All 13 cases of placental chorioangioma were detected by prenatal ultrasound . The detecting time is between 16- 36 weeks of gestetion. All of these 13 cases are single placental chorioangioma. Among the 13 cases, 76.9%（10/13）cases were showing as low-echoic lesions, 23.1%(3/13)were showing as high-echoic lesions; Color blood flow were detected in 69.2%(9/13)cases and not detected in 30.8%(4/13)cases. There are 84.6%(11/13)cases of full-term birth with chorioangioma and 15.4%(2/13)cases of mid - term induced labor . Conclutions Prenatal ultrasound is an effective method for examination of placental chorioangioma before delivery, which plays an important role in detecting placental chorioangioma as well as in monitoring fetal and placental situation in estimating fetal prognosis.