Acute Retinal Necrosis Syndrome (ARN) is a severe, vision-threatening ocular disease caused by herpesvirus infections. It is characterized by abrupt onset and rapid progression, often leading to irreversible visual impairment due to complications in the affected eye such as rhegmatogenous retinal detachment, optic atrophy, and intractable hypotony—and potential involvement of the fellow eye if not promptly diagnosed and treated. As ARN is relatively uncommon, many ophthalmologists lack sufficient experience in diagnosing ARN. In addition, its management is complex, typically involving antiviral therapy, corticosteroids, and vitrectomy. Currently, diagnostic and therapeutic approaches to ARN in hospitals across China are largely based on individual clinical experience, underscoring the urgent need for a standardized clinical protocol. To address this, the Fundus Diseases Group in Ophthalmology Branch of Chinese Medical Association and the Professional Committee of Fundus Diseases in Ophthalmology Branch of Chinese Medical Doctor Association have jointly developed Expert consensus on the diagnosis and treatment of acute retinal necrosis syndrome. The consensus is informed by a comprehensive review of the literature, the latest clinical research findings, and consideration of the current socio-economic context in China. Following multiple rounds of expert review and revision, the final version has been completed. This document provides a detailed account of ARN, covering clinical manifestations, imaging and etiological assessments, diagnostic and differential diagnostic criteria, as well as medical and surgical treatment strategies. It is intended to serve as a practical guide for both subspecialized and general ophthalmologists. Developed in accordance with the principles of evidence-based medicine and adapted to China's clinical realities, the consensus offers practical guidance for the diagnosis and management of ARN. While the proposed clinical pathway is designed to meet the needs of most patients, clinicians are encouraged to tailor treatment plans based on individual patient factors, including disease severity, therapeutic options, and economic considerations.