Objective To explore the application effect of peer-led debriefing based on the Social Learning Theory in high-fidelity scenario simulation teaching. Methods A standardized program for the application of peer-led debriefing based on the Social Learning Theory in high-fidelity scenario simulation teaching was constructed. Then a total of 44 undergraduate nursing students enrolled in 2018 were selected as participants, and 2 first-year graduate students were chosen as peer facilitators, and the program was used to conduct high-fidelity scenario simulation teaching in the course of Emergency and Critical Care Nursing. Quantitative and qualitative methods were utilized to evaluate the application effect. Results There were not statistically significant differences in the performance of students′ operation and theory between the participants and their counterparts enrolled in 2017 (both P>0.05). While after the simulation teaching, the participants′ knowledge level score was statistically significant better than that before the teaching (P<0.05), they scored 74.50 (68.00, 83.75) points for debriefing experience and 55.00 (50.50, 62.00) points for satisfaction and self-confidence in simulation learning. The results of qualitative interviews showed that, the students recognized the peer-led debriefing teaching model, and the peer facilitators′ experience was good, and their overall ability was somewhat improved. Conclusion In the simulation teaching of peer-led debriefing based on the Social Learning Theory, the students and peer facilitators have good experience of participating, so it can be used as a supplementary teaching form of simulation teaching to realize the complementary advantages of peer education and high simulation teaching, and then improve the simulation teaching effects.