Treatment of a case of widespread superficial oral squamous cell carcinoma with external beam irradiation, followed by high dose rate Microselectron mould radiotherapy, is reported. The tumor disappeared macroscopically after treatment, but there was infield recurrence in the buccogingival sulcus where the radiation dose might have been inadequate. Apart from some radiation mucositis within the treated area, edema and a superficial ulcer were observed in the tongue. These were considered to be due to radiation overdose. Although there is room for improvement, this mode of treatment has something to offer patients with hard-to-cure cancer.