We studied men were HIV-infected undergoing screening for HPV-related precancerous lesions. We analyzed the microbiota composition of biopsy and fecal samples. We obtained the total DNA from these samples and we used it as template to amplify by PCR the V3-V4 region of 16S rRNA gene.The PCR products were sequenced using MiSeq V3 (2x300 cycles)(Illumina).