The professional work of teachers is becoming more complex and demanding as teachers are expected to take on multiple roles in their daily work lives to sustain high-quality student learning to meet the expectations of different stakeholders. Many educational scholars and leaders worldwide see an imperative to empower teachers, by providing teachers with more autonomy and authority in exercising their professional judgement to perform their work effectively. Research has found that when school leaders empower teachers, it not only could increase teachers' effectiveness but also enhance their work motivation and well-being. Despite an increasing interest in teacher empowerment as a school management strategy, empirical evidence on understanding the specific empowering behaviours of school leaders and the underlying mechanisms of empowering teachers is still limited. According to the Self-Determination Theory, humans have three basic psychological needs: autonomy, competence and relatedness. The satisfaction of these three psychological needs are essential for humans to function at their optimum to experience well-being and self-actualisation. To understand the teacher empowerment process better, it is important to examine how school leaders could facilitate teachers' fulfillment of these three psychological needs. Therefore, this current study examined the mediating role of psychological needs satisfaction between perceived principal's empowering behaviours (which consists of seven dimensions: 'delegation of authority', 'providing intellectual stimulation', 'giving acknowledgement and recognition', 'articulating a vision', 'fostering collaborative relationships', 'providing individualised concern and support', and 'providing role-modelling') and job satisfaction as well as organisational commitment. A sample of 180 primary school teachers in Singapore voluntarily participated in this study by completing an anonymous written questionnaire. Data was collected and subsequently analysed through structural equation modelling. The results revealed that teachers' psychological needs satisfaction mediated between perceived principal's empowering behaviours and teachers' job satisfaction as well as organisational commitment. Interestingly, the three dimensions of teachers' psychological needs satisfaction were predicted by different dimensions of perceived principal's empowering behaviours. Specifically, the need for autonomy was predicted by 'delegation of authority', 'providing individualised concern and support', and 'providing role-modelling' and it further predicted job satisfaction and organisational commitment. The need for competence was predicted by 'giving acknowledgement and recognition' and 'articulating a vision' and it further predicted job satisfaction. The need for relatedness was predicted by 'providing intellectual stimulation', 'giving acknowledgement and recognition' and 'fostering collaborative relationships' and it further predicted job satisfaction and organisational commitment. Implications for research and practice will be further discussed.