Probiotics are live microorganisms that， when administered in adequate amounts， confer a health benefit on the host. Scientific researches have shown that probiotics can modulate the balance of human gut microbiota， attenuate constipation and antibiotic-associated diarrhea and so forth， but the health benefits of probiotics exert only when administered in adequate amounts. In this review， the clinically effective doses of probiotics on functional constipation， antibiotic-associated diarrhea and irritable bowel syndrome， the influencing factors of probiotics health benefits， and recommended intake of probiotics in the international standards or regulations was illustrated. Based on the analysis of the dose-response relationship of probiotics， the expert consensus is reached. It will help for the construction of standards and regulations of probiotics and the development of industrialization of probiotics in China.