Introduction: Diarrhea remains a major cause of death in children under 5 years are considered. However, following the overuse of antibiotics and the arbitrary use of broad-spectrum antibiotic, as well as diarrhea associated with antibiotic use is increasing. This study aimed to determine the role of probiotics in the prevention and treatments of diarrhea in children have been conducted. Materials and Methods: Search on the subject of electronic journals and databases such as Web sites SID, Iran Medex, Pubmed and Google scholr from 2010 to 2014 was conducted. Results: Food and Agriculture Organization of the United Nations as probiotic " microorganisms that have beneficial health effect on the host has sufficient volume " can be defined. Probiotics on the intestinal microbial balance improves. The most important function of probiotics , development , maturation and regulation of the secretory immune system - is mucous . Other proposed mechanisms include probiotics strengthen the immune system by strengthening tight junctions , stimulation of cytokinin production and the production of secondary materials as protective nutrients ( short chain fatty acids, arginine) for visceral action , is .Thibault and their colleagues in their study on 90 children were living in orphanages, kindergartens in France showed that days of diarrhea and daily probability of diarrhea in the probiotic group consumed significantly reduced compared with the control group. Conclusions: According to studies, due to the wide acceptance and lack of side effects of probiotics, probiotic products are increasingly the trend is rising, so it is recommended due to the high incidence of diarrhea among children in the prevention and used to treat diarrhea. Keywords: Child, Diarrhea, Probiotics.