The process of learning mathematics includes an important aspect that students must master, namely the ability to understand mathematical concepts. The conceptual understanding ability of students at SMPN 1 Pasir Penyu is still relatively low. This problem arises because learning activities tend to be teacher-centered, and there are limited opportunities for students to engage in activities that enhance their mathematical problem-solving skills. Therefore, this study aims to examine the effect of Wordwall-based learning media on the understanding of mathematical concepts among seventh-grade students of SMPN 1 Pasir Penyu. The research employed a quasi-experimental method with a Nonequivalent Control Group Design. The population consisted of all Grade VII students in the 2025/2026 academic year. The sample was selected through purposive sampling, consisting of one experimental class with 32 students and one control class with 32 students. The research instruments included a mathematical concept understanding test and validated learning tools. Data were collected using both test and non-test techniques and analyzed through descriptive and inferential statistical methods. These revealed a significant difference in the average scores of students’ conceptual understanding between the experimental and control classes after being given different treatments. Based on the results of the Independent Sample T-Test, the obtained significance value (Sig. 2-tailed) was 0.000, which is less than α = 0.05. This means that H₀ is rejected and H₁ is accepted. Therefore, it can be concluded that the use of Wordwall-based learning media significantly improves students’ understanding of mathematical concepts in Grade VII of SMPN 1 Pasir Penyu.