Objective To evaluate the effect of training mode combing Plan-Do-Check-Act (PDCA) circulation management with scenario-based simulation on first-aid quality in outpatient emergency incidents. Methods From January in 2021 to December in 2022, the outpatient nurses in Ruijin Hospital (North Branch) affiliated to Shanghai Jiao Tong University School of Medicine were selected and total 38 nurses with an of average age [(29.89±5.62) years] enrolled in the study, including 1 male and 37 females. In the same period, a total of 71 outpatient emergency incidents were selected as the research objects. All collected information was done retrospective analysis. The nurses were divided into two groups. Before January in 2022, the nurses received the first-aid training of routine mode were enrolled in pre-implementation group. After January in 2022, the nurses trained through the first-aid training of PDCA circulation management combined with scenario-based simulation (new mode) were enrolled in post-implementation group. The two groups were compared in terms of first-aid ability (theory test, basic operation examination, comprehensive first-aid ability examination), first-aid performance (start-up time, transport time, first-aid success rate, disputes/complaints rate, satisfaction score) in real emergency incidents, and self-efficacy (scores of general self-efficacy scale). Results Following the first-aid training, the post-implementation group’s scores in theory test (89.19±6.50 vs 85.11±6.84) and comprehensive first-aid ability examination (87.76±6.10 vs 84.38±5.19) as well as scores in various items of basic operation examination were significantly higher than those in pre-implementation group (P<0.001). Meanwhile, the first-aid performance in the post-implementation group showed significantly shorter start-up time [(4.89±1.24) min vs (5.56±1.19) min] and transporting time [(9.36±1.05) min vs (10.24±1.26) min], lower dispute/complaint rate (2.8% vs 17.1%) and higher satisfaction score (87.14±9.68 vs 85.11±6.84) than those in the pre-implementation group in real emergency incidents (P<0.05). In addition, the post-implementation group’s overall scores of general self-efficacy scale increased remarkably than that in the pre-implementation group (2.53±0.24 vs 2.31±0.22, P<0.05). Conclusions The first-aid training combining PDCA circulation management with scenario-based simulation can effectively enhance outpatient nurses’ first-aid ability and self-efficacy, reduce their stress and anxiety, and make them improve first-aid quality and achieve better performance in real emergency incidents.