The aim of this study is to examine the effect of Entrepreneurship-oriented STEM activities, implemented in the context of Pure Substances and Mixture, on 7th-grade students' entrepreneurship skills and perception. "Embedded design" from the mixed method designs was utilized as the research design of the study. The study group consistsed of 23 students studying in the 7th-grade of a state school in the central district of Van in the fall semester of the 2019-2020 academic year. Entrepreneurship-oriented STEM activities were implemented through six-week modules. While quantitative data on students' entrepreneurship skills were obtained using Science-Based Entrepreneurship Scale, qualitative data on entrepreneurship perceptions were obtained through structured interviews. Paired sample t-test and Wilcoxon signed rank test were used for quantitative data analysis, content analysis method was used for qualitative data. Results indicated that the mean scores of taking risk, the need of success and communication skills increased and students' entrepreneurship perceptions improved at the end of the study. As a result, it was revealed that STEM activities where entrepreneurship skills are prioritized can improve students' perception and skills towards entrepreneurship.