Gemfibrozil (GFZ) is a medication of the fibrate category with agonistic effects on peroxisome proliferator-activated receptor-α (PPAR-α) and is effective for hypertriglyceridemia and mixed dyslipidemia. This agent also has anti-inflammatory and antioxidant properties. The current study investigated the effects of GFZ on hepatorenal damages in a D-galactose (D-gal)-induced aging model. We used 28 male mice, which were equally and randomly divided into four groups as follows: normal, D-gal (150 mg/kg/day; intraperitoneal [i.p.], for 6 weeks), GFZ (100 mg/kg/day GFZ, orally [p.o.] for 6 weeks), and the combined D-gal + GFZ. Liver and kidney function indices were measured as serum creatinine, blood urine nitrogen, alanine aminotransferase, and aspartate aminotransferase. Oxidative stress in hepatic and renal tissue was evaluated through malondialdehyde, superoxide dismutase, and glutathione peroxidase levels. Finally, the liver and kidney tissues were assessed for histopathological lesions. The results showed that D-gal-induced aging leads to abnormalities in liver and kidney function indices. D-gal also induced significant oxidative stress and histopathological lesions in these organs. GFZ improved function indices and oxidative stress compared to the D-gal-treated animals. Histological evaluations of the liver and kidney also confirmed these results. These data provide evidence for the potential therapeutic of GFZ in clinical practice for mitigating the hepatorenal damages of aging.