The disease course of children with persistent or chronic diarrhea lasts from two weeks to two months or over. Diarrhea is a clinical syndrome caused by a group of multiple etiologies. This paper reviews common causes of persistent or chronic diarrhea in children, including intestinal infections, nonspecific inflammatory bowel diseases, food allergy, lactose intolerance, antibiotic-associated diarrhea, neural regulation abnormality, immunodeficiency disease, malnutrition, Celiac disease and zinc deficiency.