The aim of this study is to investigate the effect of argumentation-based teaching carried out with secondary school 7th grade students on students' scientific process skills. The sample of the study consists of 7th grade students in two different branches studying at a public school in the Central Anatolia Region of Turkey in the 2018-2019 academic year. The study was carried out with the participation of 36 students, 18 in the experimental group and 18 in the control group, and lasted approximately 12 weeks. Mixed method was used as the research model in the study. In the quantitative part of the research, the semi-experimental pretest-posttest paired control group design was used, and in the qualitative part, the semi-structured interview form developed by the researcher was used. The "Scientific Process Skills Scale" was applied to the experimental and control groups as a pre-test and post-test. At the end of the process, the scores of the students from the related test were analyzed. As a result of the research, no significant difference was found between the scientific process skill levels of the experimental and control groups.