D-galactose (D-gal) administration causes oxidative disorder and is widely utilized in aging animal models. Therefore, we subcutaneously injected D-gal at 200 mg/kg BW dose to assess the potential preventive effect of thymoquinone (TQ) and curcumin (Cur) against the oxidative alterations induced by D-gal. Other than the control, vehicle, and D-gal groups, the TQ and Cur treated groups were orally supplemented at 20 mg/kg BW of each alone or combined. TQ and Cur effectively suppressed the oxidative alterations induced by D-gal in brain and heart tissues. The TQ and Cur combination significantly decreased the elevated necrosis in the brain and heart by D-gal. It significantly reduced brain caspase 3, calbindin, and calcium-binding adapter molecule 1 (IBA1), heart caspase 3, and BCL2. Expression of mRNA of the brain and heart TP53, p21, Bax, and CASP-3 were significantly downregulated in the TQ and Cur combination group along with upregulation of BCL2 in comparison with the D-gal group. Data suggested that the TQ and Cur combination is a promising approach in aging prevention.