Background: Mastectomy mean surgical removal of all breast tissue and used as surgical treatment of breast cancer patients, follow up after surgery is very important for detecting abnormalities at the mastectomy. Aim: value of ultrasound (U/S)examination at mastectomy bed . Patients and methods: A prospective study, included 100 female patients that underwent mastectomy and attended to Benha teaching hospital for follow up examination. 10 patients excluded (as 7 patient refused to participate , 3 patient not adherent to follow up),so the finally total 90 female patients were referred for, clinical examination following U/S examination, and the final result depend on histopathological correlation or follow up 6monthes for at least one year. Results: 10 patients out of 90 had US suspicious feature and after biopsy ,8patients of them proved as recurrence. Conclusion: patients after mastectomy had risk for recurrent breast cancer so reqular Follow-up U/S examination for early detecting abnormalities at the mastectomy site.