Congenital chloride diarrhea is a rare cause of severe infantile diarrhea with excessive chloride excretion. Mutations in the SLC26A3 gene cause congenital chloride diarrhea. It generally becomes apparent in the neonatal period and is characterized by electrolyte imbalances, metabolic alkalosis, and failure to thrive. The diagnosis of congenital chloride diarrhea is based on detecting excessive chloride in the stool (90 mmol/L). We report a Turkish neonate with congenital chloride diarrhea whose sibling had the same disease. The newborn was born by cesarean delivery. Diarrhea, vomiting, and weight loss started soon after birth. She was diagnosed as having congenital chloride diarrhea based on its typical clinical signs and a high concentration of stool chloride and was confirmed by genetic analysis. She was treated by means of salt supplementations and lansoprazole. Family history may play an important role in the early diagnosis because the disease is inherited autosomal recessively.