Mirror syndrome is a rare clinical condition in pregnancy associated with significant fetal mortality and maternal morbidity. It is characterized by a triad of complications: fetal hydrops, placenta oedema, and maternal oedema. We are reporting one case of late-onset Mirror syndrome in which the patient presented later in the gestation of 36 weeks due to excessive weight gain and clinical sign mimicking preeclampsia. Awareness of this disease is essential, as a failure of recognition will delay the treatment and cause higher maternal and perinatal morbidity and mortality.