Medicinal plants have played a vital role in treatment of variety of male reproductive system disorders.Thymoquinone (TQ), is the main active components of Nigella sativa, exhibited very useful biomedical effects such as anti-inflammatory, antioxidant, antimicrobial, antiparasitic, anticancer and hypoglycemic effects.The aim of this study was to evaluate the probable protective effect of thymoquinone (TQ) on imidaclopride (IMI) induced testicular damage in rats. Forty male albino rats were classified randomly into four equal groups. Group1 (control). Group2 (IMI): rats received IMI orally day after day over a period of 8 weeks at a dose level of 21.2 mg/kg b.w (1/20 LD50). Group3 (TQ): rats received TQ orally once per day at a dose of 10 mg/kg body weight/day for 8 weeks. Group 4 (TQ+IMI): rats received TQ (10 mg/kg body weight) orally for 4 days before and along with the administration of (IMI) over a period of 8 weeks. At the end of the experiment blood samples were collected for testosterone and estradiol (E2) hormones determination,semen samples for sperm characteristics evaluation and testes for the determination of MDA, SOD, CAT, GSH and also, for histopathological examination. The obtained results reported the endocrine disruption effect of IMI resembled in marked decline in testosterone hormone, while E2 was markedly elevated. At the same time there was an insignificant reduction at sperm characteristics (motility, viability and count), while there was a highly significance elevation at sperm abnormality. Oxidative stress results showed a significant increase in testicular tissue MDA in imidaclopride intoxicated rats. However, testicular SOD activity, catalase, and GSH concentration were markedly decreased.TQ protection to IMI induced testicular toxicity in rats caused a significant improvement of all previous parameters. These results suggested possible protective role of thymoquinone to improve testicular damage by attenuating the endocrine disruptor effect of IMI on some reproductive hormones, sperm characteristics alterations or oxidative stress markers in rats through its anti-inflammatory activities and free radical scavenging properties.