Klippel-Trenaunay syndrome (KTS) is characterized by capillary and venous malformation and hypertrophy of bone and soft tissues. A 29-year-old primigravida, who had been diagnosed of KTS by her hemangiomas and varicosities in the right leg, pubic area, rectum, vagina and lower abdominal area, was scheduled to receive caesarean section at 37 weeks gestation because vaginal delivery might cause hemorrhagic complications and extension of the venous lesions. Regional anesthesia was avoided because of the possible injuries of unknown venous malformations or varicose veins in the epidural or spinal space. The cesarean section was performed under general anesthesia uneventfully and an infant was delivered normally. There were no complications such as massive hemorrhage, disseminated intravascular coagulation and deep venous thrombosis in the perioperative period. Careful anesthetic considerations for the prevention of hemorrhagic and thrombotic complications are necessary for cesarean section in a patient with KTS.