Situs inversus is a rare congenital anomaly which has the mirror image of systemic organs and vessels from their normal position. We report a case of endovascular thrombectomy for acute middle cerebral artery (MCA) M1 occlusion in a patient with complete situs inversus. A right-handed man in his 70s presented to our hospital with loss of consciousness, right-sided hemiplegia, and total aphasia. Endovascular thrombectomy was undertaken for left M1 occlusion. Guide catheter advanced through right aortic arch and injection showed innominate artery was on the left side. Left common carotid artery arose from left innominate artery. Using aspiration catheter and stent retriever, successful recanalization was achieved after three passes. For treatment of acute stroke with large vessel occlusion in patients with situs inversus, understanding anatomy and clinical features of situs inversus is important.