Objective To evaluate the effectiveness of a porcine lung-based bionic simulation system in mechanical ventilator training for junior nurses in the emergency department. Methods The ventilator application training was conducted for 22 junior nurses in the emergency department of a public tertiary hospital. An ex-vivo porcine lung was used to create a bionic teaching tool connected to a ventilator for simulated demonstrations and case-based instruction. Assessments were conducted on the trainees at three time points：before training（T0），after theoretical training（T1），and after porcine lung simulation training （T2）. Assessments included theoretical knowledge tests，operational skills tests，and the Chinese version of the Nurses’ Professional Self-Efficacy Scale. Statistical analysis was performed using one-way repeated-measures ANOVA. Results Significant differences were observed across the three time points in trainees’ scores for theoretical knowledge（F=30.791，P<0.001），operational skills（F=57.460，P<0.001），and self-efficacy（F=230.156，P<0.001）. Further pairwise comparisons revealed that the trainees’ scores at T1 and T2 were significantly higher than those at T0（P<0.05）. Moreover，operational skills and self-efficacy scores at T2 were significantly higher than those at T1（P<0.05）. Conclusion The ex-vivo porcine lung bionic simulation system is feasible for mechanical ventilator training in the emergency department. It effectively enhances trainees’ theoretical knowledge，operational proficiency，and professional self-efficacy. This study can provide a reference for optimizing training programs for emergency department nurses.