Objective To evaluate the application efficacy of infection control observer(ICO) system in operating rooms during coronavirus disease 2019 (COVID-19) epidemic period. Methods ICO system was applied to the diagnosis and treatment activities in operating rooms, epidemic-relevant procedures and guidelines of operating rooms were formulated, on the first day (February 17) after one week of work and the first day (February 24) after one week of the implementation of ICO management system during epidemic period, anxiety as well as qualified putting on and taking off personal protective equipment(PPE) of health care workers (HCWs) in operating rooms were investigated by self-rating anxiety scale (SAS) and rating scale of putting on and taking off PPE, difference before and after the implementation of ICO system were compared. Results A total of 60 HCWs were surveyed and 120 questionnaires were issued twice, 100% of questionnaires were available. Before the implementation (February 17), anxiety score of HCWs was (56.96±9.45), after the implementation (February 24), anxiety score of HCWs was (35.02±6.21), difference was significant (t=14.878, P < 0.001). Before and after the implementation of ICO system, anxiety scores of HCWs with different professional titles were all significantly different (all P < 0.05). Before the implementation of system, anxiety score of HCWs with junior professional title was lower than that of HCWs with intermediate and senior professional titles, differences were both significant (both P < 0.05). Anxiety scores of HCWs with different professional titles before and after the implementation of ICO system were all significantly different (all P < 0.001). 50 nurses in the department were grouped to evaluate putting on and taking off PPE, qualified rate of putting on and taking off PPE in group A (without the supervision and guidance of ICOs) was 40.00% (10/25), while that in group B (with the supervision and guidance of ICOs) was 100.00% (25/25), group B was higher than that in group A, difference was significant (χ²=21.429, P < 0.001). Conclusion ICO system can effectively reduce the psychological anxiety of HCWs during diagnosis and treatment activities and improve the qualified rate of putting on and taking off PPE.