Health care workers (HCWs) are at risk for suffering negative psychological consequences of the COVID-19 pandemic, such as secondary traumatic stress symptoms (STS), as they are exposed to this traumatic experience both directly, as community residents, and indirectly, in the care of infected patients. Following vicarious exposure, positive psychological outcomes, such as vicarious posttraumatic growth (VPTG), are also likely, though they are less studied. The present study aims to examine (a) the associations among STS, VPTG, and coping strategies among HCWs during the COVID-19 lockdown and (b) the mediating role of coping strategies in the STS-VPTG relationship. Cross-sectional online data were collected amid the COVID-19 lockdown in Greece (March 23, 2020 through May 3, 2020) from a sample of 647 HCWs (25% men, 75% women). The Secondary Traumatic Stress Scale, the Post Traumatic Growth Inventory, and the Brief Coping Orientation to Problems Experienced Inventory were used to measure STS, VPTG, and coping strategies, respectively. HCWs reported moderate to low levels of STS and VPTG, with the VPTG dimensions of personal strength and appreciation of life being the highest categories. Intrusions mental and both adaptive and maladaptive coping strategies predicted VPTG. Adaptive coping strategies partially mediated the relationship between STS and VPTG, whereas maladaptive coping strategies fully mediated this relationship. Understanding the coping responses during lockdown among HCWs is important for developing tailored prevention and intervention actions to protect the populations at risk from the deleterious impacts of uncontrollable and life-threatening diseases and promote posttraumatic growth. (PsycInfo Database Record (c) 2022 APA, all rights reserved).