Type B Aortic dissection in pregnancy is a rare but life-threatening disease for both mother and fetus1.It typically occurs in the third trimester of pregnancy or the early postpartum period2.The mortality of aortic dissection increases with delay in diagnosis.Most cases of aortic dissection during pregnancy have certain risk factors, including Marfan syndrome and congenital heart diseases3, we present a case of acute type B aortic dissection developing spontaneously at 36 weeks of bigeminal gestation, treated successfully by endovascular repair following immediate caesarean section.Both mother and neonate survived and recovered well.