Objectives: This study mainly explores the influence of the care leader's sincere leadership traits on the organizational citizenship behavior of nursing staff. This is a cross-sectional study, and it is convenient to sample and use a structured questionnaire to investigate. Methods: The study sample was a staff of 274 nurses with one year of experience in two regional hospitals in Tainan. The questionnaire recovery rate was 97.86%. The data were analyzed and verified by descriptive statistics, factor analysis, Pearson correlation and hierarchical regression analysis. Results: The research show: First, sincere leadership has a significant positive impact on organizational citizenship behavior. Second, It has a significant positive impact on organizational identity, organizational assistance, interpersonal harmony, public and private differentiation. Conclusions: According to the research results, the leadership traits of the nursing supervisor will affect the nursing staff's organizational citizenship behavior. When the nursing staff feels the honest leadership of the supervisor, it will positively influence the decision of the organization to take the actual action, and proposes to select and cultivate the nursing. When you are in charge, you can classify the characteristics of sincere leadership as one of the qualifications, and use this topic as a teaching material for cultivating leaders.