Five children with glucose-galactose malabsorption (GGM) are presented. Two infants from Saudi Arabia were first-degree relatives, the third infant was unrelated and the other two were of Yemeni and Syrian origin, respectively. All the infants had chronic diarrhoea and four had failed to thrive since early infancy. All had stools positive for reducing substances, and sugar chromatography showed glucose and galactose malabsorption. Small bowel biopsies were normal in all. One infant developed gangrene of both legs as a complication of hypernatraemia and dehydration, necessitating bilateral amputation. Two infants had nephrolithiasis. All the infants responded well to fructose-based formulae. GGM should be considered in the differential diagnosis of chronic diarrhoea in infants breastfed or artificially fed from early life.