Abstract: Heat stroke can result in multiple organ dysfunction syndrome (MODS), with insidious early symptoms, complicated clinical manifestations, and hence tending to be misdiagnosed. This paper reported a case of severe occupational heat illness (heat stroke) with manifestations of MODS after a 12 h continuous outdoor work without protective measures. Its clinical characteristics, effective treatment strategies, and lessons of experience were analyzed. Preventive measures were proposed consequently, intending to improve understanding and treatment of severe occupational heat illness with concurrence of MODS.