The temporomandibular joint can be dislocated during anesthesia as a result of excessive oral opening and direct laryngoscope handling. Occasionally, yawning can be observed during the induction of anesthesia with propofol. The forceful and voluntary yawning after a propofol injection can lead to a dislocation of the temporomandibular joint. We report a case of an anterior dislocation of the temporomandibular joint upon induction with propofol, which caused difficulties in mask ventilation and endotracheal intubation. Although intubation had been carried out successfully in this case, an unanticipated difficult airway can be confronted at anytime. Therefore, anesthesiologists should be aware of the management of a difficult airway and practice various Methods according to a difficult airway algorithm.