Background: Simulation in nursing has been the trend as one of the teaching modalities during laboratory session. Contemporaneous, the use of mannequin and peer simulated patient serves as a medium to depict patient in providing necessary competencies in the realm of nursing mainly in Health Assessment course. Aim: To investigate the effect of moderate-fidelity mannequin vs peer simulated patient on nursing students experience and level of competency. Method: 80 nursing students enrolled in Health Assessment course at King Saud bin Abdulaziz University for Health Science were recruited in the current study; data was collected by questionnaire and competency checklist. Results: The study results revealed that there was a statically significance difference regarding the total experience and total competency mean scores among the study and control groups (t= 10.039, P= .000 & t= 3.791, P= .000 respectively) towards the use of Peer Simulated Patient. Conclusion and Recommendation: Nowadays many nursing schools have started to utilize simulation-based nursing teaching and learning, however, simulation-based learning should be applied blended with the peer simulation in teaching to improve the undergraduate nursing students' clinical experience and assessment skills.