Squamous cell carcinoma (SCC) is the second most common type of skin cancer in Japan, and its incidence has been increasing in recent years. Early diagnosis and complete excision can provide a high cure rate. However, advanced cases of SCC showing local invasion, regional lymph node metastasis or distant metastasis are not curative and are difficult to treat with surgery alone. Some chemotherapy regimens have been used for treating advanced cutaneous SCC. However, almost all these regimens require intravenous administration and result in serious toxicities in elderly people. We gave S–1, a novel oral chemotherapeutic agent, for six patients with advanced cutaneous SCC. Three patients achieved complete response and one achieved partial response. Two patients showed stable disease. The overall response rate was 66.7% (four of six patients), and the disease control rate was 100%. Two of six patients developed grade 3 anaemia. Oral S–1 treatment is safe and effective for treating advanced cutaneous SCC. However, a prospective trial is necessary to confirm the effectiveness of oral S–1 for advanced cutaneous SCC.