The study aims to examine the effectiveness of the group-delivered revised written exposure therapy (WET-R) for post-traumatic stress disorder (PTSD) and subclinical PTSD among Chinese adolescents with a randomized controlled trial. The study will recruit 70 participants, with 35 randomized to the WET-R group and 35 randomized to the waiting list (WL) group. The WET-R intervention consists of 5-8 group sessions. The primary outcome CPSS-5-I (Child PTSD Symptom Scale-Interview Version for DSM-5) and PCL-5 ( PTSD Checklist-5) will be administered on baseline, post-treatment, 1-month follow-up, 3-month follow-up, and 6-month follow-up assessments.