The objective of this study was to compare the effect of curative 3-dimensional (3D) conformal radio-chemotherapy and intensity-modulated radiotherapy (IMRT) modalities on swallowing function in patients with nasopharyngeal cancer. Ten patients receiving 3D conformal radiotherapy and 10 patients receiving curative radiotherapy with IMRT, who were admitted for malignancy control for nasopharyngeal cancer, were included in the study. Swallowing functions were determined by flexible fiberoptic endoscopic evaluation. Premature spillage, retention pooling, penetration, aspiration, and reflex cough were evaluated. No statistically significant difference was found between patients receiving 3D conformal radiotherapy and IMRT regarding the scores of premature spillage, retention pooling, penetration, and aspiration with 3, 5, and 10 mL water and 5 mL yoghurt and fish crackers (P > .05). Velopharyngeal insufficiency or delayed onset of swallowing reflex was not found in any of the patients (P > .05). No significant difference was found between the groups in terms of the symptoms regarding subjective evaluation of swallowing (P > .05). Swallowing function did not differ among patients receiving IMRT and 3D conformal radiotherapy. Further studies with a larger sample size are warranted in order to verify the results.