Objective: To explore the current situation and interrelationship between humanistic care ability and professional identity of ICU nurses，in order to take measures to improve the ability of nurses caring for ICU management personnel and provide theoretical basis for professional identity level. Methods: A questionnaire survey was conducted on a total of 218 ICU nurses from seven hospitals in Tianjin, by caring ability inventory and nursing profession identification scale. Results: The total score of ICU nurses’ humanistic care ability was （178.06 + 30.98）, including cognitive score (71.56 + 13.92), patience score (54.54 + 9.82), courage score (51.96 + 13.37). The scores in each dimension were lower than the foreign norm. The total score of professional identity was （106.16±22.29）, at the medium level. There was positive correlation between the dimensions of ICU nurses’ humanistic caring ability and that of their professional identity (P<0.01).The linear regression analysis showed that professional identity could be predicted by the humanistic care ability of cognition and patience, after controlling demographic variables. Conclusion: For most ICU nurses, the ability to perform humanistic care and their professional identity are interrelated, and both stay a low level. Nursing managers can take measures to improve the humanistic care ability of ICU nurses and enhance their professional identity.