Carvacrol is a common ingredient in the pharmaceutical, cosmetic, and perfume industries. It possesses various pharmaceutical properties including pain relief, anti-cell death, antioxidant, anti-cancer, and anti-inflammatory effects. We investigated the protective impact of carvacrol on infertility caused by varicocele in rats. The animals were assigned to nine groups randomly: control, sham-operated, carvacrol alone at 10, 20, and 40 mg/kg b.w./day, varicocele-induced control, and varicocele-induced rats treated with carvacrol. After thirty days of treatment, the serum was collected to evaluate testosterone levels, and left epididymal sperm samples were obtained to assess sperm quality. Additionally, the left testis was removed for biochemical and histopathological evaluation. The findings demonstrated that carvacrol administration (20 and 40 mg/kg) notably improved sperm quality in rats with varicocele. Furthermore, carvacrol treatment (20 and 40 mg/kg) increased antioxidant levels, reduced MDA levels, decreased AQP