Fetal hydrothorax combined with hydrops complicating mirror syndrome is a rare obstetric pathological condition.Its pathogenesis is not clear at present.The prognosis is often poor when the symptoms are poorly controlled,even endangering both of the mother and child.There are few reports on this condition domestically and internationally,and there is no clinical guidelines for this disease.We report a case of a pregnant woman with massive fetal hydrothorax combined with hydrops complicating mirror syndrome who underwent thoraco-amniotic shunting.This procedure successfully prolonged the gestational week,improving the perinatal prognosis.This case report and the review of related literature can improve clinicians'understanding of fetal hydrops complicated by mirror syndrome.With the development of mirror syndrome,pregnant women may be complicated by preeclampsia,requiring vigilant clinical monitoring.Clinicians can improve the condition of fetal hydrops through intrauterine treatment,appropriately prolong the gestational week,and improve the prognosis of perinatal infants,and at the same time,choose hospitals with the capability of critical care for termination of pregnancy.