Malnutrition exerts an inhibitory effect on the reproductive function.The objective of this work was to study the effects of severe protein deficiency (diet 2% casein and 0% methionine) in Wistar rats prepubescent on body and testicular weight. A significant decrease in the weight happens during this phase. By the 30th day of deficiency, the animals stabilize their weight. Indicating their ability to adapt to the "stress" nutrition.Histological examination of the testes revealed a blockage in the spermatogenic lineage stage spermatids or rare sperm.After refueling (diet 20% casein and 0.3% methionine), there is recovery of body weight and glandular.We also note the lifting of the inhibition of reproductive function and distribution of spermatozoa in the lumen of the seminiferous tubules.