Successful management of temporomandibular joint (TMJ) ankylosis depends on adequate gap arthroplasty and interpositional graft; the objective is to produce a functioning pseudoarthrosis that prevents reankylosis and provides adequate mobility. Several interpositional grafts have been used for the treatment of temporomandibular joint ankylosis such as indigenous pterygomasseteric sling, temporalis muscle/fascia, auricular cartilage, fat and dermis-fat. Lateral thigh fascia lata (LTFL) graft is commonly used in neurosurgical practice and in other surgical specialities. We present a case of lateral thigh fascia lata used as interpositional graft for the treatment of a unilateral fibrous temporomandibular joint ankylosis.