Fetal polycystic kidney is mostly caused by genetic factors, but it may also be caused by genetic mutations due to drugs and other factors. Fetal polycystic kidney a common hereditary disease of the kidneys, and mainly autosomal dominant inheritance, autosomal related genes are abnormally expressed, which leads to the occurrence of polycystic kidneys, abnormal enlargement of the kidneys can be observed during pregnancy, and it is usually recommended to terminate the pregnancy once the diagnosis is clear. However, there are also some cases of fetal polycystic kidney due to the wrong use of drugs during pregnancy, which leads to the mutation of related genes, resulting in the occurrence of fetal polycystic kidney, but this case is more rare. Prenatal diagnosis is recommended if fetal polycystic kidney is found on examination in the clinic.