Objective To know the current situation of undergraduate nursing students’ career decision-making difficulties,and to analyze the correlation of career decision-making difficulties and professional social support. Methods A total of 169 undergraduate nursing interns from two universities were selected by convenient sampling. Career decision-making questionnaire and career-related social support scale were used to investigate the career decision and the occupational social support of nursing undergraduates. Results The total score of occupational decision-making difficulties of undergraduate nursing interns was（2.76±0.47）,and the total score of occupation-related social support items of undergraduate nursing interns was（3.47±0.50）. Occupational decision-making difficulties and occupation-related social support were negative correlation moderately（r=-0.417,P<0.05）. Multiple linear regression analysis showed that the occupation-related social support entered the regression equation（P<0.05）. Conclusion Undergraduate nursing interns have a medium level in career decision-making difficulties,and career decision-making difficulties is closely related to the career-related social support. Therefore,schools,hospitals,and family members should be encouraged to take corresponding measures to improve occupation-related social support and to reduce the career decision-making difficulties in order to promote the professional development of undergraduate nursing students and steady the professional team.