Aims: The purpose of this quantitative study is to determine the effectiveness of mobile gamification as an intervention in expanding the vocabulary of Grade 10 students in the Filipino subject. Study Design: The study employed a quasi-experimental research design using a one-group pretest-posttest approach to measure the changes in students’ vocabulary before and after the intervention. Place and Duration of Study: The study was conducted at Tagum City National Comprehensive High School – Pagsabangan Campus during the School Year 2025–2026. Methodology: The respondents of the study consisted of thirty (30) Grade 10 students from the Aristotle section. A researcher-made vocabulary test served as the primary instrument for data gathering. A pre-test was administered before the implementation of mobile gamification, while a post-test was conducted after the intervention. Mean, standard deviation, and dependent samples t-test were used to analyze the difference in students’ scores before and after the intervention. Results: The findings revealed that the students’ mean score in the pre-test was 19.57 with a class proficiency of 65%, described as nearing mastery level. Meanwhile, the post-test mean score increased to 26.03 with a class proficiency of 87%, described as class has attained mastery level. The results indicate a significant improvement in the students’ vocabulary level after the implementation of mobile gamification as an intervention. Furthermore, the dependent samples t-test showed a significant difference between the students’ scores before and after the intervention. Conclusion: Based on the findings, mobile gamification was proven to be an effective strategy in expanding the vocabulary of students in the Filipino subject. The use of interactive and gamified activities through mobile devices increased students’ interest, motivation, and active participation in learning.