Previous research works demonstrate that risk perception (RP) of coronavirus disease 2019 (COVID-19) may result in experiencing negative emotions. The current research sought to further appraise of whether perceived social support alleviated the negative impact of RP of COVID-19 on subjective well-being (SWB) among university students. A sum of 594 university students in China aged 16 to 25 years old completed an online questionnaire during the COVID-19 outbreak on college campuses. The results found that uncontrollability negatively predicted positive affect and satisfaction with life; susceptibility, severity, and uncontrollability positively predicted negative affect in university students. Moreover, the relation between RP of COVID-19 and SWB was moderated by perceived social support. RP of COVID-19 predicted SWB in university students with high perceived social support but not amongst those with low perceived social support. Thus, the current research indicates that RP of COVID-19 may inhibit SWB and that high perceived social support may alleviate the negative role of RP of COVID-19 in SWB in university students.