Radiotherapy can be followed by recalcitrant skin ulcers. As low intensity laser irradiation has been demonstrated to have a beneficial effect on impaired wound healing, we investigated its efficacy and safety in three patients with chronic radiation ulcers. The three patients, previously mastectomized due to breast cancer, with recalcitrant radiation ulcers of the skin were treated with a 30 mW helium-neon laser (wavelength: 632.8 nm, intensity: 3 mW/cm2, dose: 30 J/ cm2) three times weekly. In all patients, complete wound closure was achieved within a period of 7, 5, and 8 weeks. One patient died 6 weeks after laser treatment due to tumor cachexia. Neither of the other patients showed recurrence of radiation ulcers or neoplasm during a follow-up of 36 months. Low intensity helium-neon laser irradiation has been shown to be effective in the induction of wound healing in radiotherapy-induced ulcers in three patients with breast cancer.