Congenital chloride diarrhea of infancy is a life threatening disease. We discuss two boys with congenital chloride diarrhea over a long time period before and after kidney transplantation. In the first case, prenatal sonography revealed polyhydramnios and generalized bowel loop distention. The genetic study confirmed congenital chloride diarrhea of infancy. Multiple episodes of severe dehydration, hyponatremia and acute tubular necrosis were seen during the follow up period. He underwent a year of hemodialysis before kidney transplantation. Three periods of improvement concerning diarrhea occurred with the use of corticosteroids, taken for other reasons. These improvements were seen after prednisolone administration for mastoiditis and following prednisolone administration for kidney transplantation. The second case was a 3.5 year old boy who is the cousin of the first case. He was referred to hospital with chronic watery diarrhea, metabolic alkalosis, hypokalemia, hyponatremia and failure to thrive in the first year of life. He was also treated with prednisolone and showed significant improvement.