To explore the status of clinical first-line nurses' professional identity, and clarify the relationship among clinical nurses' perceived social support, professional values and professional identity, so as to provide empirical evidence for enhancing nurses' professional identity.

This study was a cross-sectional descriptive study. From February 24 to March 28, 2020, convenience sampling was used to select 1 633 clinical first-line nurses from 13 ClassⅢ public hospitals in Anhui Province and Hunan Province. This study conducted the investigation with the General Information Questionnaire, Chinese version of Nursing Professional Value Scale-Revised (NPVS-R) , Perceived Social Support Scale (PSSS) and the Professional Identity Scale, and analyzed the mediating effect of professional values in perceived social support and professional identity. A total of 1 633 nurses were surveyed, and 1 507 valid questionnaires were obtained, with an effective rate of 92.3%.

The total score of 1 507 clinical first-line nurses on the Occupational Identity Scale was 106 (26) . Mediating effect analysis showed that perceived social support directly predicted professional values (β=0.480, P<0.001) and professional identity (β=0.529, P<0.001) ; professional values directly predicted professional identity (β=0.303, P<0.001) ; perceived social support used professional values as a mediating variable to have an indirect positive predictive effect on professional identity, and its indirect effect wasβ=0.145 (P<0.001) .

The professional identity of clinical first-line nurses is at a medium level, and professional identity is positively correlated with perceived social support and professional values, and professional values play a part of the mediating role. Hospitals and nursing managers can provide social support and enhance professional values to improve nurses' professional identity.

Nurses; Professional identity; Social support; Professional values; Mediation effect