Monosodium glutamate (MSG) is a flavoring food additive that"s found in many foods like chips, and fast foods. The aim of this study was to demonstrate the injurious effects of MSG on the adrenal glands of the female albino rats and its potentiality to cross the placental barrier carrying its injurious effects to their pups. Twenty-five female albino rats weighing about (200) g were mated then separated into two groups. The control group (10 rats),and MSG-treated Group(15 rats) received 10g/kg MSG orally, dissolved in water at a concentration of 10 g/100 ml, starting on day 7 to 20 day of gestation.A day after delivery, animals were weighed, blood samples collected then sacrificed, and the adrenals were collected and examined by the light and electron microscope. Statistically, there was a significant increase in the body weight and decrease in adrenal weight of MSG-treated mothers and their pups, as well as a decrease in the corticosterone level in MSG-treated mothers. Histologically, MSG-treated mothers and pups showed many degenerative changes, with thinning of the capsule that was confirmed by Masson trichrome stain, a abnormal structure of Zona Golmeruloza and Zona Fasciculata, and areas of shedding and blood vessels were noticed. Shrunken nuclei and degenerated mitochondria with disrupted cristae and penetration of the lipid droplets to form "myelin-like" structures were noticed by E/M examination. The study concluded that MSG had an unwholesome effect on the structure of the adrenal tissue of both pregnant rats and their pups.