Plagiarism is a problematic issue in universities across the globe (Curtis & Vardanega, 2016). This study explored the relationship between negative emotionality and positive attitudes toward plagiarism through the mediation of academic self-efficacy and self-control. Negative emotionality was examined as three components: stress, anxiety, and depression. Self-report surveys were completed by 454 university students to investigate the relationship between negative emotionality and positive attitudes toward plagiarism, as well as the mediating role of academic self-efficacy and self-control in this relationship. The hierarchical multiple regression found that negative emotionality significantly predicted positive attitudes toward plagiarism over and above age and gender (i.e., where male students and younger students were more likely to plagiarise). Furthermore, three mediation analyses showed that academic self-efficacy and self-control mediate the relationship between positive attitudes toward plagiarism and each component of negative emotionality. Considering these results, subsequent research should investigate whether implementing strategies that alleviate stress, anxiety, and depression could increase academic self-efficacy and self-control, which in turn, could then reduce positive attitudes toward plagiarism.