〔Abstract〕 To explore the relationship between acne vulgaris and gut microbiota. Methods A total of 29 patients with moderate to severe acne vulgaris and 26 healthy controls were included. Fecal samples were collected, and the gut microbiota was analyzed using hypervariable regions of 16S rRNA genes through high-throughput sequencing. Results We identified associations between acne vulgaris and alterations in gut microbiota. At the phylum level,Bacteroidota was significantly higher in the acne group compared to the control group (P<0.01), while Cyanobacteria was significantly lower in the acne group (P<0.01). At the genus level, the top five different bacterial taxa in both groups were Bacteroides, Escherichia-Shigella, Klebsiella, Roseburia, and Parabacteroides. Among them, Bacteroides, Roseburia, and Parabacteroides were more abundant in acne patients. Linear discriminant analysis identified five biomarkers all belonging to the Bacteroidota phylum in the acne and control groups. These biomarkers belong to the phylum Bacteroidetes. The observed differences in genera between acne patients and healthy controls provide novel insights into the connection between gut microbiota changes and acne vulgaris risk. Conclusion Our findings reveal a significant difference in the composition of intestinal microflora between acne patients and healthy individuals, and changes in the richness of specific bacterial genera may become a new target for the diagnosis and treatment of acne.