This study set to investigate the influence of principals’ leadership styles on secondary school teachers’ career commitment in Imenti South District, Kenya. The study sought to establish whether principal’s leadership style stimulates and sustains teachers’ career commitment. The study was guided by the Transformational leadership Theory, to test whether teachers under a principal who exhibits the transformational leadership styles of initiative, consideration and participative management had higher levels of career commitment than those working under principals who did not. The dependent variable for the study was teachers’ career commitment. The independent variable was principals’ leadership styles. The intervening variables were teachers’ gender and teaching experience. The study used descriptive survey design targeting all the 54 principals and 468 teachers from the 54 public secondary schools in Imenti South district. Stratified random sampling was used to select 48 schools, from which 48 principals and 240 teachers were selected to participate in the study. Data was collected using two questionnaires, one for principals and one for teachers. Descriptive and inferential statistics were used to analyze data obtained, including frequency counts, means, percentages and ANOVA. The analysed data was presented in summary form using frequency distribution tables, bar graphs and pie charts. The study established that leadership styles of secondary school principals do not influence career commitment of teachers. However, demographic variables such as gender and working experience had an impact on career commitment of teachers. Female teachers were found to have a higher level of career commitment than their male counterparts. Novice teachers had high levels of career commitment, which declined as they stayed longer in the teaching profession before improving as they neared retirement. These findings have important implications for the structuring of careers for teachers. Since career commitment has been found to strongly correlate with turnover, the findings of this study suggest that teachers in the middle of their career (up to 10 years of work experience) may have higher intentions to quit than those with a few years of experience and those nearing retirement. It is hoped that the findings of the study will equip administrators with knowledge to influence the retention rate of teachers to the benefit the student, the teacher, and the school system.