Objective: The 8.12 Tianjin Port Explosion in 2015 caused heavy casualties.Pingjin Hospital, an affiliated college hospital in Tianjin, China participated in the rescue activities.This study aims to analyze the emergency medical response to this event and share experience with trauma physicians to optimize the use of medical resource and reduce mortality of critical patients.Methods: As a trauma centre at the accident city, our hospital treated 298 patients.We retrospectively analyzed the data of emergency medical response, including injury triage, injury type, ICU patient flow, and medical resource use.Results: There were totally 165 deaths, 8 missing, and 797 non-fatal injuries in this explosion.Our hospital treated 298 casualties in two surges of medical demand.The first one appeared at 1 h after explosion when 147 wounded were received and the second one at 4 h when 31 seriously injured patients were received, among whom 29 were transferred from Tianjin Emergency Center which was responsible for the scene injury triage.After reexamination and triage, only 11 cases were defined as critical ill patients.The over-triage rate reached as high as 62.07％.Seventeen patients underwent surgery and 17 patients were admitted to the intensive care unit.Conclusions: The present pre-hospital system is incomplete and may induce two surges of medical demand.The first one has a much larger number of casualties than predicted but the injury level is mild;while the second one has less wounded but almost all of them are critical patients.The over-triage rate is high.The hospital emergency response can be improved by an effective re-triage and implementation of a hospital-wide damage control.