An aldehyde dehydrogenase SpALDH2 from Sphingobium sp. has been discovered with the unprecedented ability to utilize oxidized nicotinamide cofactor biomimetics (NCBs_ox). Among eight NCBs_ox tested, 3-carbamoyl-1-(4-carboxybenzyl) pyridin-1-ium (p-BANA⁺) enabled 96.8% conversion of syringaldehyde, comparable to NAD⁺. SpALDH2 exhibited a k_cat/K_M of 21.418 mM⁻¹ min⁻¹ with p-BANA⁺, nearly 500-fold higher than with other NCBs_ox. Molecular docking and interaction analyses suggested that hydrogen bonding and pi–pi stacking between the para-carboxyl group of p-BANA⁺ and key active-site residues contribute to its superior compatibility. These results support SpALDH2 as a promising catalyst for NCBs_ox-mediated oxidation.