This study aims to describe students' mathematical argumentation skills in SPLDV material using the Toulmin model after APOS theory-based learning. This study is based on the low argumentation skills of students, especially in solving story-based SPLDV problems. The research method used was descriptive with 25 students from class VIII.2 of SMPN 5 North Indralaya in the 2025/2026 academic year s…