Objective: Children and adolescents are found to be more vulnerable to developing PTSD than adults over time after major disasters. This study aims to investigate the network structures of PTSD and the directions of relationships between symptoms among adolescent survivors in the year after the Yancheng Tornado in China. Method: A total of 395 youth survivors completed the Child PTSD Symptom Scale (Foa et al., 2001) at 3 months and 12 months following the tornado. Network analysis was used to compare networks of PTSD symptoms and changes over time. Results: Different centrality symptoms existed at different time points. Anger, startle responses, and physiological reactivity were important to the maintenance of PTSD symptoms arising from the tornado at 3 months, while dreams/nightmares and distancing/avoidance were important to maintaining PTSD symptoms at 12 months. Analysis suggested that sleep difficulty and intrusive thoughts were the key PTSD symptoms to be treated at 3 months; sleep remained to be the key symptoms to be treated at 12 months. Conclusions: Our findings suggest that sleep difficulty could be a main cause of other symptoms and trigger the entire symptom system into undesirable psychopathological development among adolescent survivors in the year following major disasters. (PsycInfo Database Record (c) 2022 APA, all rights reserved).