Louis Valdo-Barbey (born Valdo Louis Barbey in Valeyres‑sous‑Rances, Switzerland, 1 Nov 1880; died Paris, 5 Dec 1964) was a Swiss‑born painter, draughtsman and decorator who made his career largely in France. He trained in Paris at the Académie Julian, studying under Eugène Burnand, Jean‑Paul Laurens and George Desvallières, and became a naturalised French citizen in 1909.

Valdo‑Barbey worked across a range of subjects, from landscapes and port scenes to marine views, often characterised by solid draftsmanship and a realist‑inspired approach. He exhibited in Parisian salons in the early 20th century and travelled widely, producing works depicting places such as Marseille and Le Havre. Examples of his paintings and drawings appear in public collections, illustrating his engagement with both urban and maritime subjects.

His career was interrupted by service in the First World War, during which he was seriously wounded; he later documented his experience in a published war journal. In 1947 he was named Peintre Officiel de la Marine, a prestigious appointment recognising his contributions to marine art, and in 1955 he was made an Officier de la Légion d’Honneur.

Although less widely known today than some of his contemporaries, Valdo‑Barbey’s work reflects the breadth of early 20th‑century French art practice, bridging academic training, realist subjects, illustration, and decorative arts.