This study examined the relationship between professional effectiveness and self-awareness among 113 elementary teachers in the Division of Davao del Norte. Specifically, it aimed to determine the extent of professional effectiveness in terms of preparation and teaching planning, classroom management, knowledge of the subject matter, teaching characteristics, and interpersonal relations, as well as the extent of self-awareness in terms of knowledge, disposition, and performance. It also sought to establish whether a significant relationship exists between the two variables and to identify which domains of professional effectiveness significantly influence self-awareness. A descriptive-correlational research design was employed using validated and pilot-tested survey instruments. Data were analyzed using weighted mean to determine the level of each variable, Pearson product moment correlation to assess the relationship, and multiple regression analysis to identify predictors, all tested at a 0.05 level of significance. Findings revealed that professional effectiveness was extensive across all domains, indicating that it is oftentimes evident among teachers. Likewise, self-awareness was also extensive across knowledge, disposition, and performance. A significant and very strong positive relationship was found between professional effectiveness and self-awareness. Regression analysis further showed that professional effectiveness significantly predicts self-awareness, with knowledge of the subject matter emerging as the only significant predictor. Based on these findings, it is recommended that school leaders strengthen subject-matter expertise, promote reflective practices, and implement collaborative professional development programs to enhance both professional effectiveness and self-awareness among teachers.