This study aimed to determine the effect of social media posts and some sociodemographic characteristics on secondary traumatic stress and mental health of university students after the Kahramanmara & scedil; earthquake in T & uuml;rkiye. The sample of this cross-sectional study consisted of 509 university students. Data were collected using the Secondary Traumatic Stress Scale in a Sample of Social Media Users (STSS-SM) and the General Health Questionnaire-28 (GHQ-28). As a result of this study, it was determined that age, gender, duration of social media usage, traumatic experiences other than earthquakes, and the presence of psychiatric illness explain 12% of the STSS-SM, 14% of the GSA-28, and the STSS-SM explains 43% of the GSA-28. It was determined that social media posts made after the earthquake affected students' secondary traumatic stress and mental health. Mental health nurses should consider the use of social media as a risk factor for secondary traumatic stress, especially in their efforts to protect community mental health during disaster periods.