Objective To discuss the feasibility of Mongolian medicine pulse diagnosis in assessment of the disease situation of acute critically ill patients. Methods The clinical data of acute critically ill patients admitted in the Department of Emergency of Inner Mongolia International Mongolian Medical Hospital from December 2015 to December 2017 were retrospectively analyzed, and the role of Mongolian medicine pulse diagnosis in the evaluation of disease situations of patients with acute critical illness was observed. Results The improved early warning score (MEWS) at admission was carried out for all the patients in the Emergency Department of this hospital, 996 critically ill patients with their MEWS score ≥ 5 scores in accord with the inclusion criteria were allowed to undergo the Mongolian medicine pulse diagnosis, and of them, 654 patients showed specific changes in pulse condition. Shock appeared rapid pulse, microphygmia in pulse diagnosis of Mongolian medicine, severe anemia appeared the slippery pulse and rapid pulse in pulse diagnosis of Mongolian medicine, severe arrhythmia appeared rapid pulse and slow pulse in pulse diagnosis of Mongolian medicine, acute myocardial infarction appeared rapid pulse, weak pulse and slow pulse in pulse diagnosis of Mongolian medicine, insufficiency of heart function appeared rapid pulse and weak pulse in pulse diagnosis of Mongolian medicine, hypertension complicated with cerebral hemorrhage with forceful pulse and pulsus pulse are all suggestive of critical condition. Conclusions The specific changes in pulse condition of patients with acute critical illness in Mongolian medicine are helpful to the assessment of the patient's condition. This method can also be used as one of the tools for rapid assessment of disease situation in critical patients before going to hospital or in the hospital.