Background: Atrazine (ATR) is one of the most commonly used triazine herbicides in the world. It was found that ATR can cause adverse effects on reproductive function in both genders of several mammalian and non-mammalian species. The aim of this work was to evaluate the pubertal hormonal disruption effects of atrazine herbicide during and after its sub-chronic administration in juvenile albino rats of both sexes. Material and methods: One hundred twenty six juvenile albino rats of both sexes were used. They were divided into 3 equal groups as follow: Group I (negative control group), group II (positive control group), group III (ATR group). Each group was subdivided equally into two subgroups; male rats (subgroup a) and female rats (subgroup b). Female rats were monitored daily for vaginal opening. At the end of the 3 rd and the 6 th week of the study, 7 rats of each subgroup were submitted to estimate the serum levels of estradiol and luteinizing (LH) hormones in all rats of both sexes in addition testosterone in male rats. Then the rats were sacrificed. The testis and epididiymis in males, uterus and ovary in females were dissected and subjected to histopathological examination. The remaining rats were left without intervention for another 3 weeks served as follow up group. Results: Atrazine was found to delay puberty in male rat presented by significantly decreased levels of testosterone level and increased in the estradiol levels, impaired spermatogenesis and decrease in number and size of Leydig cells with disorganization. It also was found to delay puberty in females denoted by delayed vaginal opening, underdevelopement of the uterus, impaired folliculogenesis and ovulation in the ovaries. Three weeks of follow up resulted in partial improvement. Recommendation: more efforts are needed to limit exposure to atrazine especially in ground and drinking water. Khayal, E.E.H.M.; et al….. Abarikwu, S.O.; Adesiyan, A.C.; Oyeloja, T.O.; Oyeyemi, M.O. and Farombi, E.O. (2010): Changes in sperm characteristics and induction of oxidative stress in the testis and epididymis of experimental rats by a herbicide, atrazine. Arch. Environ. Contam. Toxicol., 58:874-882. Abarikwu, S.O.; Pant, A.B. and Farombi, E.O. (2013): Quercetin decreases steroidogenic enzyme activity, NF-κB expression, and oxidative stress in cultured Leydig cells exposed to atrazine. Mol. Cell. Biochem., 373(1-2):19-28. Ackerman, F. (2007): The Economics of Atrazine. Int. J. Occup. Environ. Health,13:441-449. Adesiyan, A.C.; Oyeloja, T.O.; Abarikwu, S.O.; Oyeyemi, M.O. and Farombi, E.O.(2011): Selenium provides protection to the liver but not the reproductive organs in an atrazine-model of experimental toxicity. Exp. Toxicol. Pathol., 63(3): 201-207. Anderson, S. A.; Pearce, S. W.; Fail, P. A.; McTaggart, B. T.; Tyle, R. W. and Gray, L. E. (1995): Validation of the alternative reproductive test protocol to assess toxicity of methoxchlor in rats. Toxicol., 15: 164. Ashby, J.; Tinwell, H.; Stevens, J.; Pastoor, T. and Breckenridge, C.B. (2002): "The effec...