Volunteers who respond to disasters play a crucial role in disaster management. However, their indirect exposure to traumatic events during their duties can adversely affect their mental health. The aim of the study was to determine the correlation among trauma centrality, coping self-efficacy, and posttraumatic growth and trauma centrality as possible mediator role in this relationship. A total of 112 disaster volunteers participated. The data were collected with a Demographic Form, the Centrality of Events Scale, the Post-Traumatic Growth Scale, and the Coping Self-Efficacy Scale. Disaster volunteers exhibited above average event centrality, high levels of posttraumatic growth, and coping self-efficacy. A positive correlation was identified among trauma centrality, posttraumatic growth, and coping self-efficacy, with trauma centrality playing a full mediating role. This study will be instrumental in better understanding the posttraumatic processes of disaster volunteers and in strengthening coping capacities, guiding the implementation of preventive and protective psychosocial interventions.