The number of studies on post-traumatic stress disorder after hospitalization in a pediatric intensive care unit raised since 2004. The objective of this systematic review was to summarize and critically examine the literature about risk factors for these children to develop post-traumatic stress disorder following admission to an intensive care unit. The data sources were PubMed, Cochrane, Web of Science, PsycInfo, SUDOC, Scopus, and ScienceDirect. Studies were selected if they were in English or French and published between 01/01/2004 and 31/01/2022. Studies were excluded if patients were less than 1 month old and if no post-traumatic stress disorder was found. The internal validity and risk of bias were assessed using the National Institutes of Health Study Quality Assessment Tools for observational studies and the Ottawa Scale was used for the interventional study. The search yielded 523 results and 22 articles met inclusion criteria. Three common risk factors were identified from the data: parental post-traumatic stress disorder (especially in mothers), severity of illness and delusional memories. Internalizing behavior in children, acute parent and child stress, emergency admission and sepsis are also potential risk factors that require further investigation. The prevalence of this pathology is substantial (between 14 and 36%) and increasing awareness among pediatricians and psychologists seems necessary. Prevention programs are being studied to reduce the incidence of post-traumatic stress disorder in this population. Child and adolescent psychiatry liaison should collaborate with pediatric teams to support this objective.© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany.