The gut microbiota plays a significant role in male reproductive function, influencing sperm quality, testicular structure, sex hormones, and sexual behavior. This review explores the impact of gut microbiota and its metabolites on male reproductive health from five perspectives: sperm quality, testicular structure, sex hormones, sexual behavior, and probiotic supplementation. Gut microbiota can improve sperm quality by secreting metabolites or regulating host metabolites, and it can also regulate sex hormone levels through enzyme synthesis and enterohepatic circulation, affecting the hypothalamic-pituitary-testis (HPT) axis. Metabolites from gut microbiota can activate brain areas controlling sexual arousal and behavior. Probiotic supplementation has been shown to improve male reproductive function. However, the exact mechanisms by which gut microbiota affects male infertility remain unclear. The review highlights the importance of gut microbiota in regulating male reproductive function and suggests that further research is needed to better understand these mechanisms. Probiotics, fecal microbiota transplantation (FMT), and other microbiota-based therapies are potential treatments for male infertility. The gut microbiota may also influence sexual behavior through the gut-brain axis. Overall, the gut microbiota has a significant impact on male reproductive health, and further research is needed to fully understand its role.The gut microbiota plays a significant role in male reproductive function, influencing sperm quality, testicular structure, sex hormones, and sexual behavior. This review explores the impact of gut microbiota and its metabolites on male reproductive health from five perspectives: sperm quality, testicular structure, sex hormones, sexual behavior, and probiotic supplementation. Gut microbiota can improve sperm quality by secreting metabolites or regulating host metabolites, and it can also regulate sex hormone levels through enzyme synthesis and enterohepatic circulation, affecting the hypothalamic-pituitary-testis (HPT) axis. Metabolites from gut microbiota can activate brain areas controlling sexual arousal and behavior. Probiotic supplementation has been shown to improve male reproductive function. However, the exact mechanisms by which gut microbiota affects male infertility remain unclear. The review highlights the importance of gut microbiota in regulating male reproductive function and suggests that further research is needed to better understand these mechanisms. Probiotics, fecal microbiota transplantation (FMT), and other microbiota-based therapies are potential treatments for male infertility. The gut microbiota may also influence sexual behavior through the gut-brain axis. Overall, the gut microbiota has a significant impact on male reproductive health, and further research is needed to fully understand its role.