Previous studies have reported that construing a traumatic event as central to one’s life story and identity are associated with posttraumatic growth (PTG). Due to cross-sectional designs, these studies provide only weak evidence of a causal relationship between event centrality and PTG. The main aim in the present study is to examine the longitudinal associations and directionality between centrality of event and PTG in ministerial employees who were present at work during the 2011 Oslo bombing attack (N = 229). By applying a cross-lagged autoregressive model, the present study investigates both stability across time, possible time-lagged effects, and the relationship between centrality of event and PTG at 1 and 2 years after the bombing. The results showed that levels of centrality of event and PTG were stable across time. There was a significant association between centrality of event and PTG both 1 and 2 years after the bombing; however, this relationship attenuated over time. No time-lagged effects in either direction were found. The present findings are in line with previous findings indicating that centrality of a traumatic event is related to PTG. However, the present longitudinal data do not support a hypothesis about a long-term causal effect of event centrality on PTG. Rather, the relationship between centrality of event and PTG are concurrent, and attenuates with time.