Irritable bowel syndrome (IBS), a prevalent functional gastrointestinal disorder, exhibits multifactorial origins. Recent research indicates that dysbiosis, an imbalance in gut bacteria, plays a pivotal role in IBS pathogenesis. Dysbiosis may trigger gut immune system activation, influencing various factors relevant to IBS. This review underscores the evolving significance of the gut microbiome in IBS and evaluates evidence supporting current and prospective microbiome-based treatments, shedding light on promising avenues for therapeutic interventions.