We reviewed the clinical records of 7 patients with anal squamous cell carcinoma(SCC)to evaluate the effectiveness of radical chemoradiotherapy(CRT). The radiotherapy(RT)consisted of 40 Gy delivered to the pelvis and bilateral inguinal lesions, and a perianal booster dose of 20 Gy, in fractions of 2.0 Gy per day, 5 days per week. 5-fluorouracil(5-FU)and mitomycin C(MMC)were administered 3 times every 4weeks as standard chemotherapy. On the first day of RT, 750mg/m2 of 5-FU in the form of a continuous 24-hour infusion, for 5 days was administered. On the first day of chemotherapy, 10mg/ m2 of MMC was also administered as a single bolus infusion. One patient with a T3 tumor was administered oral TS-1 during RT because of advanced age. In the CRT group, there was 1 case each of T1 and T3, and the others were T2. Grade 2 adverse effects occurred in 5 patients, and Grade 3 in 2, but completion of CRT was achieved in all 7 patients. All patients had a complete response in the anal lesion after CRT. Three patients, including those with the T3 tumor treated with TS-1, developed recurrence of the anal lesion. Two patients with T2 tumors, who were treated with CRT comprising 5-FU and MMC, developed recurrence of the anal lesion more than 60 months after CRT. CRT is expected to be a safe and effective treatment to improve the prognosis for anal squamous carcinoma; however, sufficient and appropriate follow-up is necessary after a complete response.