This study determined the effect of Game-Based Learning (GBL) on the mathematics performance of Grade 7 learners at Pavia National High School during School Year 2025–2026. Using a quasi-experimental pretest-posttest control group design, seventy learners were divided equally into experimental and control groups. A validated 40-item researcher-made test measured learners’ mathematics performance. Statistical tools included mean, standard deviation, and t-tests. Findings revealed that both groups initially demonstrated low mathematics performance with no significant pretest difference. However, posttest results showed significant improvement, with the GBL group achieving higher mathematics performance than the traditional group. Results indicate that GBL is an effective instructional strategy for improving engagement and academic achievement in mathematics.