Emerging evidence suggests that many conventional anticonvulsants, such as carbamazepine, phenytoin, and valproic acid, could cause cross-resistance to nondepolarizing muscle relaxants. However, there are few reports describing the interactions between levetiracetam and rocuronium. This case report describes the delayed onset of rocuronium in an adult patient with intractable epilepsy on long-term levetiracetam therapy. A 33-year-old man was scheduled for extraction of third molars and restorative dental treatment. His daily levetiracetam was continued preoperatively, and after a slow mask induction, rocuronium (20 mg; 0.66 mg/kg) was administered. Muscle relaxation was monitored by train-of-four (TOF) stimulation using the adductor muscle of the thumb. However, it took more than 9 minutes to finally obtain a TOF count of 0. This case report highlights that patients with intractable epilepsy taking levetiracetam may have resistance to rocuronium and should be carefully monitored to avoid harm triggered by prematurely initiated intubation maneuvers.