This mixed-methods study examines the effects of neonatal intensive care unit (NICU) scenario-based simulation training on third-year nursing students' perceived stress, learning satisfaction, self-confidence, and simulation-based learning experiences. All eligible participants will receive a high-fidelity simulation session involving a NICU scenario that includes therapeutic communication with a postpartum mother, neonatal emergency intervention, and support for mother-infant interaction. The simulation protocol consists of prebriefing (3 minutes), environmental orientation (3 minutes), scenario-based simulation (10 minutes), and debriefing using the PEARLS model (30 minutes). Quantitative data will be collected before and after the simulation using validated scales. Qualitative data will be gathered through semi-structured focus group interviews following the simulation. The study aims to provide evidence on the effectiveness of NICU simulation-based education in nursing training.