BACKGROUND Myocutaneous flap of the rectus abdominis filling the perineal defect after APR.. Abdominoperineal excision of the rectum (APR) remains the only potential curative treatment for very low rectal adenocarcinoma and squamous cell carcinoma of the anus. Yet, it implies a significant perineal exenteration and has set the attention on the perineal reconstruction. OBJECTIVE To present technique used in one case of APR for anal cancer, with resection of the vaginal posterior wall with large perineal defect which has called for the necessity of a flap for reconstruction. METHODS To cover the large perineal defect and reconstruct the posterior vaginal wall was perform a standardized and reproducible surgical technique using oblique rectus abdominis myocutaneous (ORAM) flap. The overlying skin of this flap is thick and well vascularized by both superficial branches and perforators of the superior epigastric artery and the deep inferior epigastric artery which serves as the vascular pedicle for the ORAM flap. RESULTS This procedure was applied in a 65-year-old woman with recurrent squamous cell carcinoma of the anus infiltrating the posterior wall of the vagina. Was performed an APR with en-bloc resection of the vaginal posterior wall in order to achieve tumor-free margins. Postoperative course was uneventful and she was discharged home at postoperative day 9. Final pathological report confirmed the oncological adequacy of the procedure (R0) and showed a rypT4N0 lesion. CONCLUSIONS Flap reconstruction is an effective way to cover the perineal wound reducing both perineal complication rate and wound healing delay. The ORAM is particularly interesting for female whose tumors require resection and subsequent reconstruction of the posterior wall of the vagina.