Objective To explore the mediating effect of patient privacy protection on ethical sensitivity and prosocial behavior of nursing students, and to provide a reference for taking targeted measures to improve prosocial behavior of nursing students. Methods A total of 543 nursing students from 6 first-class hospitals in Hunan province were selected as the survey objects by convenient sampling method, and the Chinese version of the Ethical Sensitivity Questionnaire for Nursing Students, Patient Privacy Scale and the Prosocial Tendencies Measure were used to investigate. Results The scores of privacy protection ability, ethical sensitivity and prosocial behavior of nursing students were 111.58±13.18, 39.75±6.88 and 95.79±15.69, respectively. Ethical sensitivity was positively correlated with patients′ privacy protection ability and prosocial behavior, and patients′ privacy protection ability was positively correlated with prosocial behavior (all P<0.05). The ability to protect patients′ privacy plays a partial mediating role between ethical sensitivity and prosocial behavior, and the mediating effect accounts for 41.89% of the total effect. Conclusion The privacy protection ability, ethical sensitivity and prosocial behavior of nursing students are at or above the medium level, and the protection of patient privacy plays a partial mediating role between the ethical sensitivity and prosocial behavior of nursing students. It is suggested that schools and hospitals should take targeted measures to improve the patient privacy protection ability and ethical sensitivity of nursing students, and improve their prosocial behavior, so as to improve the quality of nursing services.