Aims: Identify characteristics acute and chronic of radiotherapy cutaneous injuries in experiments and clinic through analysis clinical characteristics, histology and bacterial culture. Methods: Experimental studies on 30 rats to doses of pure white ulcers and assessment of acute phase injury characteristics in rat. Clinical study on 42 patients with skin lesions caused by radiation treatment at National Institute of Bums Le Huu Trac from 8/2008 to 8/2011. Information obtained: reasons for radiation treatment, radiation location, complications, bacterial culture and histology. Results: histological images of an acute ulcer in experiment: intact structure in rat skin, acute inflammatory images, together with cell damage by radiation such as acute inflammation of endothelial blood vessels, morphological changes of fibroblasts. In clinic: average age: 39 percent 22, female/male = 2.8/1, time for injury occurence: the earliest appear in the process of radiation, the latest appear more than 19 years late. Patients with chronic phase: 69.06 percent, and third degree of injury with rate of 47.61 percent. Local complications: muscle injuries: 28.58 percent, bone injuries: 14.28 percent. High infection rate: 96.77 percent. Histological images at chronic phase: Skin structure change such as: atrophia cutis, reduced or complete lass of skin appendages, thrombosis in blood vessel, collagen proliferation. Conclusion: Skin lesions after radiation therapy is quite special, they appear immediately after radiation therapy, but clinically found in chronic phases with long term chronic ischemia, high infection rates, more severe complications.