Variations and anomalies of upper extremities have been commonly reported in routine dissection, clinical practices, and cadaver studies. Despite ongoing research on arterial variations of upper extremities, the absence of bilateral ulnar artery is extremely rare with only 3 patients reported. As the authors are presenting a successfully treated patient, initially prepped for radial forearm osteocutaneous free flap for treatment on oromandibular defect after a wide resection of head and neck cancer lesion, being confirmed to have bilateral ulnar artery hypoplasia and due to this, the patient had to change her surgical plan to fibular osteocutaneous free flap.