A 5.8 magnitude earthquake hit Gyeongju City, South Korea, in 2016, traumatising and psychologically panicking residents. The purpose of this study was to identify predictive factors for posttraumatic growth (PTG) among university students who experienced South Korea's largest earthquake. A cross-sectional descriptive survey was distributed to a convenience sample of 493 university students in Gyeongju City. Data were collected via 5 self-report questionnaires. PTG was found to be positively correlated with posttraumatic stress disorder (PTSD), resilience and social support. Multiple regression analysis showed that PTSD (β = 0.519, p < .001), resilience (β = 0.213, p < .001), religion (β = 0.125, p = .001) and sex (female; β = 0.090, p = .010) were identified as predictive factors of PTG. These results illustrate a need for health care providers to include individual internal resources such as resilience in intervention strategies to promote PTG and decrease posttraumatic experiences in those who have experienced traumatic events such as earthquakes. A longitudinal study is needed to obtain more definitive evidence of PTSD progression and PTG over time.