The prenatal diagnosis of pericardial tumor is extremely rare. It may have serious consequences such as massive pericardial effusion, cardiac tamponade, hydrops fetalis and fetal demise. We present a case of nonimmune hydrops fetalis secondary to pericardial mass which was successfully treated in utero by serial pericardiocentesis. Also, we present a review of the literature regarding the intrauterine interventions performed in pericardial tumor cases. At 24 weeks' gestation ascites, diffuse subcutaneous edema at the thorax and abdomen, scalp edema and two masses within severe pericardial effusion were detected. After the pericardiocentesis performed at 25, 28 and 29 weeks' gestation, ascites and scalp edema resolved, and the pericardial effusion regressed gradually. The size of masses did not change throughout the gestation. After the infant was born at 37 weeks' gestation, the masses shrunk spontaneously within five months. [ABSTRACT FROM AUTHOR]