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Stable aldehyde dehydrogenases (ALDH) from extremophilic microorganisms constitute efficient catalysts in biotechnologies. In search of active ALDHs at low temperatures and of these enzymes from cold-adapted microorganisms, we cloned and characterized a novel recombinant ALDH from the psychrotrophic <i>Flavobacterium</i> PL002 isolated from Antarctic seawater. The recombinant enzyme (F-ALDH) from this cold-adapted strain was obtained by cloning and expressing of the PL002 <i>aldH</i> gene (1506 bp) in <i>Escherichia coli</i> BL21(DE3). Phylogeny and structural analyses showed a high amino acid sequence identity (89%) with <i>Flavobacterium frigidimaris</i> ALDH and conservation of all active site residues. The purified F-ALDH by affinity chromatography was homotetrameric, preserving 80% activity at 4 °C for 18 days. F-ALDH used both NAD⁺ and NADP⁺ and a broad range of aliphatic and aromatic substrates, showing cofactor-dependent compensatory <i>K</i>_M and <i>k</i>_cat values and the highest catalytic efficiency (0.50 µM⁻¹ s⁻¹) for isovaleraldehyde. The enzyme was active in the 4–60 °C-temperature interval, with an optimal pH of 9.5, and a preference for NAD⁺-dependent reactions. Arrhenius plots of both NAD(P)⁺-dependent reactions indicated conformational changes occurring at 30 °C, with four(five)-fold lower activation energy at high temperatures. The high thermal stability and substrate-specific catalytic efficiency of this novel cold-active ALDH favoring aliphatic catalysis provided a promising catalyst for biotechnological and biosensing applications.