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Purpose: To report a novel case of Paracentral Acute Middle Maculopathy (PAMM) Secondary to Retinal Artery Macroaneurysm. Methods: A case report. Results: A 72‐year‐old lady presented with three‐month history of sudden onset left paracentral scotoma. Her medical history include hypertension and hyperlipidemia. Visual acuity was 6/7.5 and 6/45 in the right and left eye respectively. Anterior segment examination and intraocular pressures were unremarkable. A ruptured retinal arterial macroaneurysm (RAM) was seen along the second‐order artery along the inferotemporal arcade with a small area of deep‐retinal whitening along the distal branches of the artery. Corresponding optical coherence tomography showed a round superficial retinal hyperreflective lesion consistent with RAM and hyperreflective band involving the outer plexiform layer (OPL), inner nuclear layer (INL) and inner plexiform layer (IPL) consistent with PAMM. Confocal scanning laser ophthalmoscopy video fluorescein angiogram (FA) demonstrated a ruptured and hemorrhagic RAM with significantly delayed distal filling of the artery, with resultant PAMM in an area supplied by the tributary arterioles of the affected artery. Conclusions: Oxygen consumption is highest at the metabolically active middle retinal layer. The inner and middle retinal layers are supplied by the superficial capillary plexus in the ganglion cell layer, intermediate capillary plexus (ICP) in the INL‐IPL boundary and deep capillary plexus (DCP) in the INL‐OPL boundary. Rupture and partial thrombosis of the RAM resulted in mechanical narrowing of the vessel lumen and severe flow limitation, which was further exacerbated by her history of hypertension and hyperlipidemia. This was consistent with the FA findings of delayed filling in the distal parts of the artery. Flow limitation results in decreased blood supply to the retinal capillary plexuses, further decreasing perfusion pressure, causing most disruption to the delicately balanced ICP and DCP blood supply of the middle retinal layer. Middle retinal infarction occurs most readily and presents as PAMM in our patient. In conclusion, we described a novel case of PAMM secondary to a ruptured and partially thrombosed RAM which clearly elucidates the anatomy and physiology of retinal capillary plexuses. [ABSTRACT FROM AUTHOR]