Objective To introduce the independent outpatient unit mode and explore its role in the department of respiratory and critical care medicine during the outbreak of coronavirus disease 2019 (COVID-19). Methods The independent outpatient unit mode of the Department of Respiratory and Critical Care Medicine in Changhai Hospital, Naval Medical University (Second Military Medical University) was started on Jan. 31, 2020 (after the Spring Festival holiday). A total of 5 377 outpatients of this department from Jan. 13, 2020 to Jan. 23, 2020 (10 working days before the Spring Festival holiday) and 702 patients from Jan. 31, 2020 to Feb. 12, 2020 (10 working days after the Spring Festival holiday) were respectively selected. There were 10 doctors and nurses who worked both before and after the operation of independent outpatient unit in our Department. Medical indicators such as the number of outpatients and the number of patients who had a COVID-19 epidemic history, infection control indicators such as spatial density of patients and protection and control of medical staff, and the psychological status of medical staff such as anxiety were compared before and after the operation of the independent outpatient unit. Results The number of outpatients in the Department of Respiratory and Critical Care Medicine was 5 377 before the operation of the independent outpatient unit (10 days before the Spring Festival holiday), which was 15.31% higher than that in the same period of 2019 (4 663). The number of outpatients in the 10 days after the Spring Festival holiday was 702, 86.94% lower than that before the Spring Festival, and 83.43% lower than that in the same period of 2019 (4 236). The number of patients with COVID-19 epidemic history before and after the operation of independent outpatient unit was 25 and 0, respectively (χ²=2.26, P>0.05). The waiting time of outpatients decreased from (178.33±36.24) min before operation to (8.50±3.59) min after operation (t=10.18, P<0.01). The total proportion of acute upper respiratory tract infection and acute bronchitis was 46.61% (2 506/5 377) and 34.90% (245/702), respectively (χ²=34.9, P<0.01). The proportion of cough with unknown reason was 2.42% (17/702), which was significantly lower than the former (5.41% ［291/5 377］) (χ²=11.54, P<0.01). There was no significant difference in the proportion of acute exacerbation of chronic obstructive pulmonary disease and acute attack of asthma before and after the operation of independent outpatient unit (both P>0.05). The proportion of prescribing medicine for chronic obstructive pulmonary disease and bronchial asthma was 29.34% (206/702), which was significantly higher than the former (15.23% ［819/5 377］) (χ²=88.23, P<0.01). The density of patients in the diagnosis and treatment area decreased from (1.85±0.35)/m² to (0.31±0.08)/m² (t=10.52, P<0.01). There were 7, 7, 5 and 10, 10, 10 medical staff who followed the standard of hand hygiene and wearing mask and work cap before and after the operation of the independent outpatient unit respectively (all P>0.05). The anxiety score of medical staff decreased from (38.33±2.79) before the operation of independent outpatient unit to (33.61±2.38) (t=4.97, P<0.01). The satisfaction of the medical staff with the protective measures increased after the operation of the independent outpatient unit than before (9 vs 4), and the difference was statistically significant (χ²=20.00, P=0.03). Conclusion The independent outpatient unit mode of the department of respiratory and critical care medicine is a feasible and optimized mode of outpatient service during the outbreak of COVID-19. It could meet the needs of outpatients, shorten the waiting time, and improve the occupational protection of medical staff. It is also helpful to reduce cross infection and improve the level of prevention and control of nosocomial infection.