Jejunal diverticula are extremely rare and even less in children and adolescents. Certain diseases such as Marfan’s syndrome, cystic fibrosis and other genetic disorders may however predispose patients to diverticular disease at a younger age. Clinically they may be asymptomatic or may give rise to complications such as chronic abdominal pain, malabsorption, hemorrhage, diverticulitis, obstruction, abscess formation and rarely diverticular perforation. We report a case of peritonitis due to perforation of non-congenital diverticulum of first jejunal loop in a 15 year old girl. The cause of perforation was penetration of diverticular wall by vegetable fiber (dried leaf rosemary). This case report highlights the rarity of acquired jejunal diverticulosis in children as well as the peculiar manner of perforation.