We report a case of local recurrence of rectal cancer that achieved complete response with high-dose interstitial brachytherapy. The patient was a forty-nine-year-old woman. In September 1995, she underwent abdominoperineal resection of rectum for rectal cancer (T4 N2 M0, moderately differentiated adenocarcinoma). In February 1996, she complained of genital bleeding. MRI examination revealed a mass of 70 x 22 x 20 mm in the pelvis, which was diagnosed to be recurrent rectal cancer with needle biopsy. Interstitial brachytherapy (60 Gy/twelve fractions/six days) was performed, and a complete response was achieved. One year after the treatment, no tumor was detected in the pelvis. No skin erosion, skin ulcer, urinary cystitis, nor ileitis occurred. High-dose interstitial brachytherapy delivers high-dose irradiation to a tumor while keeping the dose to the surrounding normal organs at a low level. This procedure may be an effective modality for local recurrence of rectal cancer.