The objective of the study was to explain the role of academic optimism, academic emotions and school well-being on the mathematical performance of girl and boy students. The research method was descriptive and correlation. A sample of 440 (109 boys and 331 girls) students was selected by cluster random sampling. The research instruments were Student Academic Optimism Scale (Tschannen-Moran, Bankole, Mitchell & Moore), Academic Emotions Questionnaire (Pekrun, Goetz & Frenzel), and School Well-being Questionnaire (Konu, Alanen, Lintonen, & Rimpela). A teacher- made questionnaire was also used to evaluate math scores. The data were analyzed by using descriptive statistics, Pearson correlation, stepwise multiple regression analysis and independent t- test. Findings showed that academic optimism, academic emotions and school well-being had significant positive correlation with math performance (0.20, 0.23, 0.16). The results showed academic well-being had significant positive relationship whit mathematic performance of girls and boys and predicts mathematic performance, too. Also, the results showed academic emotions had significant positive relationship with students mathematic performance in the girls and in combination with academic well-being explained %16 mathematic performance; but it was not the case in the boys. Academic optimism with academic well-being could explain %17 of boys mathematic performance, while in the girls there were not such explanation power.