The goal of this study is to assess the factors influencing HRM on teacher performance among selected private basic schools in the Sunyani municipality. The study used descriptive survey research designs to collect data from a sample of 246 private school teachers selected from 4 private primary schools in the municipality to participate in the study. Data is collected using questionnaires coded and tabulated for accuracy, reliability and ease of analysis and presentation using the SPSS software program. The research revealed that all HR practices included in the model i.e.training design, performance management and performance appraisal measures are significant predictors of teachers’ performance confirming the previous studies. However, the variable compensation of teachers found significant in improving the teachers’ performances. The main factors the study revealed that influenced management of the schools include management support, competition or pressure among private schools, financial resources availability, institutional requirements and availability of competent teachers. The study recommends to the management of the private schools to, as a matter of urgency, develop institutional HRM policy framework that will guide the schools in the development of competent and knowledgeable worker force to contribute to the achievement of the institutions’ goals. Such HRM policy framework should highlight more on training, performance management, performance appraisals and compensation.