Background: Head and neck cancer (HNC) is a significant public health problem over the world. Head and neck squamous cell carcinomas are the sixth most common malignancy worldwide. Radiation therapy (RT) is a corner stone in the treatment of HNC. Aim and objectives: The aim of this study was to analyze the dose distribution in the middle ear structures in patients with HNC after RT and to evaluate the dose effect on the occurrence of middle ear toxicity. Patients and methods: This prospective study was carried out in Clinical Oncology and Nuclear Medicine Department in Zagazig University Hospitals. It included 24 patients with HNC treated with RT and dose distribution to the middle ear was calculated using dose volume histogram parameters to detect the correlation between the dose and the toxicity. Results: Patients with HNC treated with RT are associated with an incidence of middle ear toxicity in the form of otitis media with effusion and eustachian tube dysfunction depending on the mean dose to middle ear and ET D30. The toxicity is associated with middle ear mean dose ≥40Gy and ET D30 >52.75Gy. Head and neck tumors above the larynx are associated with a higher mean dose to middle ear than tumors of larynx and hypopharynx. Conclusion: RT in cases of HNC is associated with middle ear toxicity and the incidence of the toxicity depends on the dose of radiation to middle ear. And the dose depends on the site of the tumor.