Objective: Under the assumption that the ulnar artery is the predominant blood supply to the hand, radial forearm free flaps (RFFF) generally have been preferred over ulnar forearm free flaps (UFFF) in head and neck reconstruction. The objective of this study is to create the first and only systematic review of the literature regarding UFFF in head and neck reconstruction, assessing the usage, morbidity, complications, and rationale of its use. Methods: A systematic review of the literature was conducted using PubMed, including Mesh terms and manual searches. Articles not in English were excluded. Results: Seventeen articles of the 80 articles identified by our search criteria met inclusion criteria; a total of 682 cases of UFFF were identified, including our patient case. Fifty-five percent of the cases involved use of the Allen's test. Mean flap size was 6.1 × 10.5 cm. Of the 432 cases reporting flap survival, 14 (3.2%) flap losses were reported, 13 total (3.0%), and one partial (0.2%). The UFFF was preferred to the RFFF due to decreased hirsutism (61%), better cosmetic outcomes (91%), and better post-operative hand function with reduced donor site morbidity (73%). For the case report, an UFFF was used successfully for lid reconstruction and resurfacing in a 72-year-old man who presented with late ectropion and exposure keratopathy following maxillary resection for leiomyosarcoma. Conclusions: This is the first and only systematic review of the literature to date of UFFF in head and neck reconstruction. Our review demonstrates that the UFFF rarely results in flap loss, donor site morbidity, or hand ischemia, instead providing enhanced outcomes. With its many surgeon-perceived advantages and minimal morbidity, the UFFF may become a preferred forearm flap for head and neck reconstruction. © 2013 Wiley Periodicals, Inc. Microsurgery 34:68–75, 2014.