COVID-19 has caused psychological problems in all age groups since it emerged from the first day. One of the most important groups has been affected negatively during the COVID-19 pandemic process are university students. One of the negative situations caused by the pandemic process in university students is student stress caused by COVID-19. To assess stress situations in Italian culture, the COVID-19 student stress scale (CSS-S) has been developed. In this context, the aim of this study was to adapt the CSS-S into Turkish. Another aim of the study was to investigate the direct and indirect relationships of COVID-19 student stress with school burnout, depression and subjective well-being. The participants of the study were 485 Turkish university students. The values obtained with the confirmatory factor analysis revealed that the factor structure of CSS-S is satisfying (
χ
2
/df = 2.99, AGFI = .95, TLI = .93, CFI = .96, IFI = .96, REMSEA = .06, SRMR = .04). Moreover, it was found that school burnout has a mediating role in the relationship between COVID-19 student stress and depression and subjective well-being (
χ
structure of CSS-S is satisfying/df = 2.41, AGFI = .87, TLI = .91, CFI = .91, IFI = .91, REMSEA = .05, SRMR = .05). These findings imply that psychosocial intervention studies to reduce COVID-19 student stress can reduce students' school burnout and depression. It also implies that these psychosocial intervention studies can have a positive impact on students' subjective well-being.