Public school teachers possess low levels of research competence, which contributes to poor action research production. Moreover, limited studies have been conducted on enhancing the action research competencies of public school teachers in the Philippines. Therefore, this study aimed to improve the action research competencies of public school teachers through an online educational research training program that included research templates, coaching, and mentoring sessions. A practical action research design was employed, involving sixty-four public school teachers who voluntarily participated in and completed the five-day training. Action research competencies were assessed before and after the training using a validated questionnaire developed by field experts, while semi-structured interviews were conducted to gather suggestions for improvement. Statistical analyses such as the median, interquartile range, Wilcoxon signed-rank test, and rank biserial correlation were performed using Jamovi version 2.4.14, and thematic analysis was applied to the interview transcripts. The findings indicated significant improvement in participants’ action research competencies, as a statistical difference was observed between pre- and post-training results. However, several suggestions were made, including allotting more writing time with peer review activities, conducting face-to-face sessions with more examples for each section of a research manuscript, and allowing a longer duration for proposal presentations. As an output, twelve action research proposals were submitted to supervisors for critique. The study was limited to one city and included only public school teachers. Therefore, it is recommended that DepEd officials continue to enhance public school teachers’ action research competencies through online or face-to-face educational research training programs to promote the production of action research addressing educational issues and challenges in schools.