Abstract Triage is the initial stage in providing immediate and suitable emergency nursing care and addressing clinical complaints. Clinical reasoning is the thinking technique that health professionals employ in their work to determine the optimal solution for each patient. The study aimed to assess the effect of a triage training program on nursing interns' clinical reasoning using immersive virtual simulation. Research design used was one-group pretest-posttest. Setting: The present study was conducted at the critical care and emergency nursing skill lab at the Faculty of Nursing, Sohag University. Sample: 80 nursing interns of the Faculty of Nursing at Sohag University. Tools: three tools were used; Structure interview questionnaire, START triage observational checklist, and clinical reasoning skills assessment scale. Results: the majority of the participants were male, with an average age of 23.40 ± 0.97 years. Furthermore, more than half (60%) did not receive any triage training. Also, after integrating immersive virtual reality, the mean scores for knowledge, practice, and clinical reasoning increased. Furthermore, there was an overall positive correlation between clinical reasoning, knowledge, and practice-related triage (p = 0.020 and 0.000, respectively). Conclusion: Immersive virtual reality can help students to improve knowledge, practice, and critical reasoning skills. Recommendations: Using immersive virtual simulations in various clinical problems and nursing education.