Aim: To determine the effects of high- and low-fidelity simulators on student nurses' learning of heart and lung sounds. Background: Simulation is an important part of nursing education because it helps to improve patient care and provides patient security. Method: The sample consisted of 3rd and 4th year students who studied at a nursing faculty in Istanbul between April and June 2017. In this randomized controlled experimental study, students were randomly divided into 2 groups, the high-fidelity simulator group (HFS group, n = 36), and the low-fidelity simulator group (LFS group, n = 35). Results: The auscultation skill levels of the HFS group were significantly higher post-training in comparison to the pre-training measurement (P < .05). There were no significant differences in the auscultation skill levels of the LFS group between the pretest and posttest measurements. Conclusion: The use of high-fidelity simulators is more effective in the learning of heart and lung sounds by student nurses than low-fidelity simulators.