Many children with physical disability have feeding difficulties. In cases of children with cerebral palsy, feeding difficulties can be seen in abnormal oral motor activity and defective swallowing coordination. These problems originate from neurological lesions. The purpose of this study was to investigate the effect of trunk and neck position on the following aspects of swallowing: stages of oral preparation, pharyngeal swallowing reflex, pharyngeal clearing and aspiration. Sixteen subjects with quadriplegic cerebral palsy were examined to assess their swal-lowing ability using videofluoroscopy(VFS). Subjects were evaluated in four different positions 1) trunk erect with the neck flexed 30°2) trunk reclined 30°posteriorly with the eck positioned neutrally 3) trunk reclined 30°posteriorly with the neck flexed 30° 4) trunk in supine with the neck flexed 30°. Friedman's test was used to analyze the effect of posi tion of the neck and trunk on swallowing. The results were as follows: 1. Ability of oral preparation was significantly better with the subject's trunk recli-ned 30°posteriorly and the neck flexed 30°than with the trunk erect and the neck flexed 30°(p < 0.05). 2. Ability of pharyngeal clearing was significantly better with the subject's trunk er-ect and the neck flexed 30° than in supine with the neck flexed 30°(p < 0.05). 3. Incidence of swallowing reflex was not significantly different among the four posi- tions (p >0.05). 4. Prevention of aspiration was significantly better with the subject's trunk reclined 30°posteriorl y and the neck flexed 30° than with the trunk reclined 30°posteriorly and the neck neutrally positi oned or in supine with the neck flexed 30°(p < 0.05). These results suggest that positions of both the neck and the trunk have an effect on swallowing in children with cerebral palsy. The position with the trunk reclined 30°posteriorly and the n eck flexed 30°was found to be optimal for oral preparation and prevention of aspiration. Further research to study swallowing ability in conjunc- tion with respiratory function is indicated.