This study investigated the mediating role of self-directed learning readiness in the relationship between project-based learning and physics problem-solving skills among Grade 10 students in public schools in Mati City, Davao Oriental. A quantitative research design utilizing descriptive and correlational approach was employed. The study involved 193 Grade 10 students from four public secondary schools. The study used mean, standard deviation, Pearson correlation, and Sobel test to analyze project-based learning, self-directed learning readiness, and problem-solving abilities in physics, addressing various research questions on their relationships and mediation effects. Findings indicated high levels of engagement in project-based learning, physics problem-solving skills, and self-directed learning readiness among the participants. Statistical analysis revealed significant relationships between project-based learning and physics problem-solving skills, self-directed learning readiness and physics problem-solving skills, and project-based learning and self-directed learning readiness. Moreover, self-directed learning readiness was found to significantly mediate the relationship between project-based learning and physics problem-solving skills. These results highlight the importance of fostering both project-based learning and self-directed learning readiness to enhance students’ problem-solving skills in physics.