The current research studies quercetin's potential to attenuate its effects on adult male rats' codeine-induced reproductive disorders. Twenty-four male adult rats were separated into four sets, consisting of six male adult rats in every set, and a 56-day treatment was obtained. General, the first set is control, and the second set (Q1) obtained quercetin using a gavage needle administered at a specific dosage (300 mg/kg/day). In contrast, the third set (Q2) obtained codeine(50mg/kg/day) using a gavage needle, and the fourth group (Q3) obtained quercetin and codeine until 56 days. As a result of exposure to codeine, the rats› blood concentrations of luteinizing hormone (L.H.) and testosterone (T.) decreased. Nevertheless, the administration of quercetin caused an elevation in the levels of (L.H.) plus (T.) hormones in the set (Q3) compared with the set (Q2). In group (Q2), there were changes in the testicle›s structure and tissue, mainly in the Sertoli cells. In addition, there was amyloid accumulation inside the seminiferous tubules; these cells were disarrangements and lacked germ cells. Meanwhile, rats given quercetin (Q1) showed improvement in testicular histopathological abnormalities. The present study›s findings, taking quercetin with codeine (Q3), demonstrated that quercetin consumption can attenuate the harmful influences of exposure to codeine on male reproductive function. In conclusion, this study investigated quercetin›s capability to protect rat testis from the histological damage that codeine causes by oxidative stress.