A total of 43 patients with severe motor and intellectual disabilities were enrolled in videofiberscopic investigation of laryngeal abnormalities. Their ages ranged from 2 to 41 years (mean: 19.9 years) and all of them had severe quadriplegia due to cerebral palsy or other conditions. Thirty-two out of the 43 patients (74.4%) had laryngeal abnormalities;laryngeal stenosis including that of iatrogenic origin, hypersecretion and laryngomalacia. Direct visualization of the occurrence of aspiration could be achieved in some patients. Seven (87.5%) out of 8 patients with tracheostomy and 25 (71.4%) out of 35 patients without tracheostomy had laryngeal abnormalities, showing no significant difference. The prevalence of abnormalities was significantly higher in patients with parenteral nutrition (30/33 = 90.9%) than in those with oral feeding (2/10 = 20%). Endoscopic investigation of the larynx is important, and videofiberscopy is especially effective for evaluation of laryngeal abnormalities in severely handicapped patients.