Klippel-Trenaunay Syndrome (KTS) is a rare genetic vascular disorder characterized by a limb affected by varicose veins, port wine stains, and hypertrophy of bone and soft tissue. It can also present with vascular malformations in the gastrointestinal tract, liver, spleen, genitourinary tract, and heart. We present a 27-year-old case of KTS diagnosed in adulthood associated with recurrent venous thromboembolism and gastrointestinal bleeding.