Objective: The primary objective of our investigation was to perform a comprehensive systematic review, aiming to establish the association between gut microbiota, Immunoglobulin A vasculitis (IgAV), and IgAVN (IgA vasculitis nephritis). Design: A systemic review. Method: A comprehensive review was performed using five electronic databases, including Medline (through PubMed), Scopus, Embase, Cochrane, and Web of Science was conducted from inspection up until 21 March 2023, to detect the studies which assessed the gut microbiota variation in HSP and HSPN patients. Results: Microbial diversity, richness and composition in HSP patients is decreased compared to the healthy control group, also HSP patients display a different microbiota structure and show a significant difference in Taxological abundance between HSP and health control which is differ from one level to another; At the phylum level: Bacteroidetes, fusobacteria and Blastocladiomycota were more abundant, At the class level: Bacteroidetes were more abundant, At the order level: Bacteroidetes were more abundant in the HSP group. Stage and site of HSP involvement effect on microbiota. GIT involvement is characteristic by increase in the abundance of Streptococcus and Fusobacteria and decrease in Faecalibacterium. Kidney involvement is characteristic by increase in the abundance of Streptococcus spp which can be used as indicator of disease severity. Escherichia-Shigella used as diagnostic for recurrence HSP because its abundance is higher than primary HSP. Conclusion: Gut microbiota can be used to detect the severity, recurrency and the site of HSP infection throw its diversity, richness and the abundant of certain microorganism which can be specify for a certain condition.