Job satisfaction remains until this date a prominent factor that managers seek in their employees to ensure the organization's productivity and success. It has extensively drawn the attention of researchers in the educational field to inform policymakers and school leaders of its impact on teachers' motivation, commitment, stress, retention, and burnout levels. The aim of this study is twofold. First, it will investigate teachers' job satisfaction level in Lebanon, and second, it will look at their perceptions of their principals' self-efficacy levels. A total of 133 Teachers Job Satisfaction Questionnaires (TJSQ) were collected from 6 private and 6 public K-12 schools to measure teachers' perceptions about the factors that are mostly correlated with their job satisfaction levels. Despite that, overall means of intrinsic factors were higher than extrinsic factors, correlation analysis revealed that extrinsic factors (i.e., working conditions and professional development) were more associated with teachers' job fulfillment. Findings from this study support the literature indicating that when teachers' extrinsic needs are fulfilled in less developed countries, they will uplift their job satisfaction level. Further implications for research and practice are also discussed.