• Background: Chronic radio dermatitis is a frequent side effect of radiotherapy. It may be associated with decreased quality of life. Aims: The aim of this study was to evaluate the clinical efficacy and safety of intralesional injection of triamcinolone acetonide for the treatment of patients with chronic radio dermatitis. Methods: This study was a prospective clinical trial conducted on 30 patients who attended to oncology outpatient clinic in Sohag University Hospital with chronic radiodermatitis.Informed consent was signed by all patients. The patients were subjected to preliminary  assessment  including  a  detailed  medical  history,  general  and  local  examination.  All patients were examined and the grade and severity of grade of radiation induced fibrosis was determined by palpating and comparing thickness, density, firmness, fixation or retraction of the irradiated skin to contralateral non-irradiated skin. The patients were subjected to intralesional steroid of diluted triamcinolone acetonide. The injection was carried out by dermojet and spaced at 1 cm interval. Injection was done every 2 weeks and for 3 months. Results: We found that 23.3% of patients had no response, 26.7% with one grade response (slight improvement), 3.3% had two grades response (moderate improvement), while 46.7% recorded complete improvement.   Conclusion: Intralesional injection of triamcinolone acetonide is an effective and safe modality for treatment of chronic radio dermatitis.