The co-existence of horseshoe kidney (HSK) and abdominal aortic aneurysm (AAA) is rare and demands a special diagnostic workup and a meticulous surgical procedure. Ten patients with HSK associated with AAA are reported. All underwent aortic replacement with successful preservation of multiple renal arteries. One patient died at the 7th postoperative day from myocardial infarction. HSK does not represent a contraindication for aortic repair. Angiography for identification of aberrant renal arteries and classification into three types for surgical management is mandatory. In type I and II we recommend a standard midline transperitoneal approach. Only in type III does a thoraco-abdominal approach seem favourable. The aortic reconstruction should be performed with tube grafts, if possible. Aberrant renal arteries are reattached directly to the prosthesis. Dissection of renal isthmus should be avoided. Temporary cold renal perfusion is indicated to extend the ischemic tolerance time. As repair of a ruptured AAA in patients with HSK may be quite difficult and time consuming, we recommend more liberal indications for aneurysm surgery in patients with HSK.