Objective To construct the competency evaluation index system of clinical mentors with master of nursing specialist. Methods Literature review,questionnaire survey,and behavioral event interview were used to initially construct the index system. Delphi method was used to conduct two rounds of expert consultation for 21 experts,and the indicators were screened and modified to determine the competency evaluation index system. Results The positive coefficients of the two rounds of expert consultation were 84.0% and 95.2% respectively. The degree of expert authority was 0.857 and 0.902. The Kendall harmony coefficient was 0.320 and 0.480 respectively（P<0.001）. Finally,6 first level indexes,19 second level indexes and 40 third level indexes were determined. Conclusion The competency evaluation index system of clinical instructors with master of nursing specialist is scientific and reliable,which can provide reference for the selection and training of clinical instructors.