Aim: The aim of this narrative review was to provide a comprehensive summary of the characteristics of gastrointestinal (GI) involvement in the most common paediatric primary vasculitides. Methods: We used PubMed to primarily identify papers, reviews, case series and editorials published in English from 2000 until 31 January 2020. Based on this, we report the prevalence, clinical manifestations, diagnostic approaches and management of GI involvement in each vasculitis. Results: Vasculitides are inflammatory blood vessel diseases, and the majority can affect the GI system with vascular, GI tract or solid organ involvement. GI involvement can sometimes complicate and delay the correct diagnosis. Clinical findings are usually nonspecific symptoms, such as fever, abdominal pain, nausea, vomiting and diarrhoea. Bleeding should alert paediatricians to the possibility of severe complicated vasculitis. Diagnosis relies mostly on imaging. If it goes unrecognised, GI involvement in paediatric vasculitis is a serious cause of morbidity and even mortality, related to bowel ischaemia and perforation. Treatment of GI symptoms depends on the type of vasculitis and usually involves high-dose steroids and immunosuppressants. Conclusion: GI manifestations in the most common paediatric primary vasculitides were usually nonspecific, diagnosis mostly relied on imaging, and treatment usually involved high-dose corticosteroids and immunosuppressants. K E Y W O R D S childhood, gastrointestinal involvement, immunosuppressant, steroids, vasculitis | 2227 TRAPANI eT Al. paralytic ileus, mesenteric ischaemia, bowel obstruction and perforation. Occasionally, GI involvement can be the presenting feature, and this can complicate and delay the correct diagnosis. The aim of this narrative review was to provide a comprehensive summary and update of the characteristics of GI involvement in the most common paediatric primary vasculitis. 2 | ME THODS We used PubMed to primarily identify papers, reviews, case series and editorials published in English from 2000 until 31 January 2020. The keywords included the following: IgA vasculitis, Henoch-Schonlein purpura, Kawasaki disease, Behcet disease, polyarteritis nodosa, Takayasu arteritis, deficiency of adenosine deaminase 2, antineutrophilic cytoplasmic antibodies-associated vasculitis, gastrointestinal, gut, child and paediatric or paediatric.