The thrust of this study was to determine the level of supervisory strategies of administrators, leadership competencies and job performance of teachers. It also investigated the mediating effect of leadership competencies on the relationship between supervisory strategies of administrators and job performance of teachers. Descriptive correlation method was applied in the study involving 400 public elementary school teachers reaching five years in service, as respondents. These teachers evaluated their school head’s leadership competencies and supervisory strategies and their own job performance through a questionnaire. Survey was conducted in the public elementary schools within Region XI. The study found that the level of supervisory strategies of administrators and leadership competencies were high and the job performances of teachers were very high. Shown also in the findings were the significant relationship of the supervisory strategies of administrators and job performance of teachers, leadership competencies and job performance of teachers, and supervisory strategies of administrators and leadership competencies. Moreover, when leadership competencies interfere in the relationship, there was partial significant relationship between supervisory strategies and job performance of teachers.