Post-traumatic stress disorder (PTSD) is a delayed onset and persistence of an individual’s catastrophic response after experiencing, witnessing, or encountering one or more actual deaths involving self or others, or the threat of death, or serious injuries, or threats to somatic integrity.The incidence of PTSD has been reported inconsistently, with women more likely to develop PTSD than men.The core symptoms of PTSD There are three groups, namely traumatic re-experiencing symptoms, avoidance and numbing-like symptoms, and heightened alertness symptoms. However, the clinical presentation is not identical in children and adults, and some symptoms are unique to children. The diagnosis can be made by these symptoms. 1.Traumatic re-experiencing symptom mainly manifests as repeated and involuntary emergence of trauma-related situations or contents in the patient’s thinking, memory or dream, and may also have severe reactive reactions, or even feel as if the traumatic event is happening again. 2.Avoidance and numbness symptoms Mainly manifested by patients’ long-term or persistent avoidance of events or situations related to traumatic experiences, refusal to participate in related activities, avoidance of traumatic places or trauma-related people or events, some patients even appear selective amnesia, unable to recall the details of trauma-related events. 3.Symptoms of increased alertness Mainly manifested as excessive alertness, increased startle response, may be accompanied by inattention, increased irritability and anxiety. 4.Other symptoms Some patients may also show addictive substance abuse, aggressive behavior, self-injurious or suicidal behavior, etc. These behaviors are often manifestations of the patient’s psycho-behavioral coping style. Also depressive symptoms are common concomitant symptoms in many PTSD patients. 5. Symptom characteristics of PTSD in children Traumatic re-experiencing symptoms in children can be manifested as nightmares, repeatedly re-enacting traumatic events, playing games with trauma-related themes, being emotional or sad when faced with relevant cues, etc. Avoidance symptoms in children are often manifested as separation anxiety, clinginess, reluctance to leave parents; High-vigilance symptoms in children are often manifested as excessive startle response, high vigilance, The symptoms of hypervigilance in children often include excessive startle response, high alertness, attention deficit, irritability or rage, and difficulty sleeping. The manifestations of PTSD may also vary among children of different ages.