Objective To explore the mediating effect of intern nursing students′ moral sensitivity and humanistic caring ability in the relationship between the cognition and behavior of protecting patients′ privacy, and to provide reference for the development of measures to improve their behavior of protecting patients′ privacy. Methods A total of 498 nursing interns from 5 tertiary hospitals in Shandong province were investigated by using the Caring Ability Inventory (CAI), the Moral Sensitivity Questionnaire for Nursing Students (MSQ-NS) and the Patient Privacy Scale (PPS). AMOS24.0 software was used to establish structural equation model for path analysis. Results The scores of humanistic care, moral sensitivity, and the cognition and behavior of protection of patient privacy were (197.57±28.74), (59.60±5.53), (117.09±12.85), (111.58±21.49). There was statistical difference between the cognitive and behavioral score of protecting patient privacy among nursing interns (P＜0.05). The total score of the intern nursing students′ patient privacy protection cognition and behavior were positively correlated with humanistic care ability and moral sensitivity (both P<0.05). Moral sensitivity and humanistic care ability had parallel mediating effect between cognition and behavior of protecting patients′ privacy, and the mediating effect accounts for 44.41% of the total effects. Conclusion There is a certain gap between intern nursing students′ behavior and cognition of protecting patients′ privacy. Nursing educators can enhance the moral sensitivity and humanistic care ability of the nursing interns, and enrich the awareness of protecting patient privacy, so as to improve the ability of nursing interns to protect patient privacy.