Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder characterized by abdominal pain, abdominal distension, and abnormal bowel movements. Its pathogenesis involves multiple factors such as imbalance of gut microbiota, immune activation, and dysfunction of the gut-brain axis. Although conventional therapies can alleviate symptoms temporarily, the limitations such as drug side effects and insufficient efficacy persistence have made microbial-targeted therapy a research hotspot. Probiotics are live microorganisms and have been proven to be beneficial to human health. Studies have shown that probiotics inhibit pathogen adhesion through competitive colonization, regulate immune responses, and repair the intestinal barrier function through metabolic products, thereby improving intestinal motility and osmotic balance. This review discusses the specific effects and potential pathways of probiotics on constipation, diarrhea, abdominal pain and distension, and mental symptoms in IBS patients. However, the clinical application of probiotics still faces challenges, including strain heterogeneity, host individual differences, and the lack of standardized treatment plans. In the future, it is necessary to combine multi-omics technologies to screen biomarkers, develop individualized intervention strategies, and optimize efficacy through dynamic monitoring, which are expected to provide more precise microbial-targeted therapy for the treatment of IBS.