The authors experienced a case of huge antronasal polyp. A 22 year-old male was admitted on Nov. 7th 73 with chief complaints of cheek swelling, exophthalmos, nasal stuffiness and bloody rhinorrhea which had gradually developed for about 5 months prior to entry. Anterior rhinoscopy revealed granulation tissue like mass in the right nasal cavity which was enlarged to push nasal septum to the left side. X-ray findings of the paranasal sinus showed wide destructive change at the maxillary antral wall on the right. Histopathological study revealed acute and chronic infected nasal polyp. The polyp mass was removed by Caldwell-Luc's approach. The postoperative course is excellent until now.