Objectives: In ensuring public welfare with primary medical and health services,the primary medical staff faces new tasks.Increasing workload,and therefore degrees of stress and buout,can influence job satisfaction and lead to presenteeism,which is defined as the appearance to be on the job but not actually working.The purpose of this study is to investigate the current worling situation and the relationship between presenteeism and mindfulness of primary medical staff and determine the mediating effect of self-efficacy on this relationship.Method: A cross-sectional survey was performed with 580 primary medical staff from 9 hospitals in Shaanxi province,northwest China.Presenteeism,mindfulness,and self-efficacy were measured by using a general information questionnaire,the Five-Facet Mindfulness Questionnaire,the General Self-Efficacy Scale,and the Stanford Presenteeism Scale.Mediating effect was analyzed by a series of hierarchical multiple regressions.Results: A high level of presenteeism was found among 47.4％ of the study participants.Presenteeism was negatively correlated with mindfulness(r--0.409,P ＜ 0.001) and self-efficacy(r--0.678,P ＜ 0.001).A positive correlation was found between mindfulness and self-efficacy(r-0.584,P＜ 0.001).When controlling for self-efficacy (β =-0.018,P＞ 0.05),the association was insignificant between presenteeism and mindfulness.Conclusion: The results identified the effect of mindfulness on presenteeism of primary medical staff is realized through self-efficacy,which also suggested to enhance self-efficacy on center location when developing management strategies for mental health education or training among primary medical staff.