Oscar Stettiner (1878 – 1948) was a British art dealer, based in Paris, and whose art collection was "seized and auctioned during the Nazi occupation of France."
Oscar Stettiner was born in 1878, the son of Henri Jules Stettiner and his wife Gertrude Davis. He had an older brother Alphonse, born in 1876, and a sister, Adele Stettiner, born in 1880. Oscar and Alphonse had British nationality; Adele French, and they were of Jewish ancestry.
Stettiner's collection included Amadeo Modigliani's 1918 portrait, Seated Man With a Cane, now the subject of a series of lawsuits involving billionaire art dealer David Nahmad and other Nahmad family members, being brought by Stettiner's grandson Philippe Maestracci.