SummaryWhile the prevalence of terrorism has increased substantially, there is a paucity of research on the effects of terrorism on employee behavior at work. Building on conservation of resources (COR) theory, and its extension, the conservation of social resources theory, we close gaps in the literature by investigating the effect of fear of terror on increased job burnout over time, the mediating effect of insomnia, and the moderating effect of supervisor and co-worker support on these relationships. This longitudinal study followed a large sample of Israeli employees (n = 670) across three time measurements over 7 years, in a time period characterized by a high number of terror attacks. The results showed fear of terror to be related to elevated job burnout over time, even during a period in which terror attacks were reduced substantially. Further, insomnia mediated the relationship between fear of terror and increased burnout, while co-worker support, but not supervisor support, moderated the relationships between fear of terror and increased insomnia and between increased insomnia and increased burnout. The results further support the notion of loss cycles in COR theory, as well as the importance of social resources, which are the cornerstones of conservation of social resources theory.