Background Complex health care environments present moral dilemmas for clinical nurses and nursing students that challenge their professional development as well as their physical and mental health. Ethical sensitivity (ES) is seen as a prerequisite that enables clinical nurses to make appropriate ethical decisions when facing a dilemma; therefore, ES should be a development focus for nursing students. Purpose The aim of this study is to conduct a systematic evaluation of existing instruments to assess moral sensitivity (MS) or ES in nursing students. We subsequently provide recommendations of the proper research tools that can be used in future studies based on our study results. Methods A systematic literature search across nine databases from their inception to November 17, 2024 was first conducted. Two researchers then independently screened these studies, which were published in English or Chinese. The studies evaluated were designed to develop or validate a scale used to measure ES or MS among nursing students. The COnsensus-based Standards for the Selection of Health Measurement INstruments (COSMIN) guidelines were followed to evaluate both the methodological quality and the quality of the psychometric properties of the identified tools. Finally, data synthesis was performed. Results We ultimately included 13 assessment tools used for the assessment of ES or MS among nursing students. Only one tool was rated A, and four tools were rated C and not recommended for use. The remaining tools were rated B, and they have potential for assessing MS and ES among nursing students. Conclusion A majority of the tools included in this study still require further revision to enhance their quality prior to their effective use in MS and ES assessments. The COSMIN guidelines indicated that future studies should describe the development and validation of measurement tools in detail and improve their current data analysis methods.