Purpose <p>To describe a case of three rare cerebral arterial variations: (1) accessory posterior cerebral artery (PCA), (2) duplicate origin of the middle cerebral artery (MCA), and (3) accessory anterior cerebral artery (ACA) diagnosed by magnetic resonance angiography (MRA).</p> Methods <p>An 80-year-old man with complete right hemiplegia underwent cranial magnetic resonance imaging (MRI) and MRA using a 3-Tesla scanner. MRA was performed using a standard three-dimensional time-of-flight technique.</p> Results <p>MRI revealed acute infarction of the left frontal lobe. MRA showed occlusion of the anterior branch of the left MCA. Subsequently, transarterial thrombectomy was performed. Six days later, follow-up MRA was performed, and a well-recanalized left MCA was confirmed. In addition, accessory right PCA supplying the parieto-occipital branch of the PCA, duplicate origin of the right MCA, and accessory ACA arising from X-shaped ACA, which is an absent variation of the anterior communicating artery (ACoA), were confirmed.</p> Conclusion <p>An accessory PCA, which typically supplies the temporal branch of the PCA, usually arises from the ACoA. We diagnosed the first case of a combination of three rare cerebral arterial variations. Careful observation using MRA is important for the detection of rare arterial variations. Volume-rendering MRA images are useful for identifying superimposed arteries.</p>