Jean-Paul Flandrin was a French painter. He was the younger brother of the painters Auguste Flandrin and Jean-Hippolyte Flandrin.

Flandrin first trained with Antoine Duclaux (a landscape painter and animal painter from Lyon) and Jean-François Legendre-Héral (a sculptor), before joining the École des beaux-arts de Lyon, then the École des beaux-arts de Paris. He then joined the studio of Dominique Ingres. He competed for the prix de Rome twice and was unsuccessful both times, but still managed to get to Rome at his own expense, joining his brother Hippolyte, who had already won the prize. They spent four years in Rome, during which Paul specialized in landscape painting, making studies after nature which he later worked up into history paintings for the Paris salons. He also regularly collaborated with his brother, providing the landscape backgrounds for the latter's works.

As well as being one of the most notable proponents of the classical landscape tradition alongside Édouard Bertin and Alexandre Desgoffe (whose daughter Aline he married in 1852), Paul Flandrin evolved later in his career towards a more naturalistic style. He also produced portraits in oils and pencil as well as caricatures. He and Aline Desgoffe had one child, Joseph Flandrin (1857-1939), who became an architect and was the father of the painter Marthe Flandrin (1904-1987).]