Previous reports revealed that increased oxidative stress with up-regulated inflammatory proteins and apoptotic factors have serious implications in busulfan-induced chemo-brain and testicular damages. Hence, we investigated the potential reversal effects of kolaviron (KV), a neuro-active extract rich in flavonoids with proven antioxido-inflammatory and anti-apoptotic properties, on busulfan-induced oxidative damage, inflammatory proteins, and apoptosis in the brains and testes of male rats. In the treatment-regimen, animals in groups 1 and 2 had saline (10 ml/kg/p.o./day) and dimethyl sulfoxide (DMSO; 10 ml/kg/p.o./day), group 3 received KV extract (200 mg/ kg/p.o./day), group 4 was given busulfan (50 mg/kg/p.o./day) and animals in group 5 were pretreated with busulfan (50 mg/kg/p.o./day) successively for 56 days in addition to KV extract (200 mg/kg/p.o./day) from days 29-56. Non-spatial memory function was valuated with a novel-object recognition memory test. Thereafter, testicular and brain oxidative/antioxidant status, proinflammatory-and apoptotic-related proteins, testicular enzymatic markers were evaluated respectively. Kolaviron extract improved cognitive function by increasing exploration of novel-object of busulfantreated rats. Kolaviron extract reversed busulfan-mediated increased malondialdehyde, 8-hydroxy-2′-deoxyguanosine, and decreased superoxide dismutase, catalase, glutathione, and glutathione-peroxidase in brains and testes as well as the testicular enzyme markers. Increased brain and testicular weights, and TNFα, IL-1β, and NFκβ productions due to busulfan administration were also reduced by the extract.The reduced testicular B-cell lymphoma-2, sperm mitochondrial cytochrome-C, and membrane potential, increased DNA fragmentation, caspases -3 and -9 levels were also profoundly reversed by KV. Additionally, KV extract ameliorated busulfaninduced testicular histopathological changes in rats. Conclusively, KV extract reverses busulfan-induced neuroendopathobiological derangements via oxidative stress inhibition, down-regulation of inflammatory and apoptotic mediators in rats' brains and testes.