13-year old boy with spastic quadriplegia cerebral palsy visited dental clinic with chief complaints of mouth breathing and malocclusion. His mouth was constantly open at the resting position, with his mandible and tongue displaced downward. He breathed through his mouth, making a constant gurgling sound, a sign of upper airway obstruction. To enhance his mandible position, vertical chin cap was first considered, but it was not sufficient to reduce the gurgling sound or ease breathing. Then, cervical splint was considered, which effectively decreased the gurgling sound by repositioning his mandible to the anterior-superior position. Oxygen saturation was increased when the cervical splint was used. Cervical splint can effectively assist breathing in patients with cerebral palsy, but it should be carefully applied as long-term use can result in unexpected complications. Under instruction by a physician regarding proper usage, a cervical splint can be applied to assist breathing in patients with cerebral palsy.