This study investigated the influence of managerial competencies and performance of teachers in upper primary in selected public schools in Mayuge District. The study used a descriptive cross-sectional survey design to examine the relationship between managerial competences and teacher performance. A sample of 92 respondents was categorized as school managers, head teachers, teachers, and management committee members. The study used simple random techniques and purposive sampling techniques. The study analyzed quantitative data collected using structured, closed-ended items in questionnaires and coded using a five-point Linkert response scale. Raw data was analyzed using descriptive statistics and Pearson product moment correlation to determine the influence of managerial competences on the performance of teachers. The study found out that managers' managerial competencies play a role in influencing the performance of teachers in public primary schools. Level of education, professional qualification of head teachers, and managerial human relations competencies all influence performance. The study concluded that poor managerial technical competences affect the performance of teachers in a negatively in form of less preparation of schemes of work and lesson planning, not following the timetable, and many others. The study recommended that there is need to encourage professional growth and training in both managerial technical competences and human relations competences in order to improve the performance of teachers in the schools. The study further recommended that for Managerial competences and performance of teachers to be effective in upper primary schools, head teachers should continue to motivate their teachers to improve on their performance, the school should hire external expertise that can facilitate professional development experiences and external expertise.