This paper provides a field report on a fire that broke out on January 26, 2018 at Sejong Hospital in Miryang, South Korea, engendering the establishment of a committee to investigate the hospital fire response. This field report analyzes the disaster medical response. The official records of the disaster response from each institution were examined. On-site surveys were conducted through interviews with government officials and other health care workers regarding communication during the disaster response without using a separate questionnaire. All medical records were abstracted from hospital charts. There were 192 casualties: 47 victims died, seven were seriously injured, and 121 suffered minor injuries. Emergency Medical Services (EMS) arrived three minutes after the fire started, while news of the fire reached the National Emergency Medicine Operation Center based in Seoul in 12 minutes. The first disaster medical assistance team (DMAT) was dispatched 63 minutes after the National Emergency Medicine Operation Center was notified. The disaster response was generally conducted in accordance with disaster medical support manuals; however, these response manuals need to be improved. Close cooperation among various institutions, including nearby community public health centers, hospitals, fire departments, and DMATs, is necessary. The response manuals should be revised for back-up institutions, as the relevant information is currently incomplete.